title
Google Python Class Day 1 Part 3

description
Google Python Class Day 1 Part 3: Dicts and Files. By Nick Parlante. Support materials and exercises: http://code.google.com/edu/languages/google-python-class

detail
{'title': 'Google Python Class Day 1 Part 3', 'heatmap': [{'end': 836.543, 'start': 655.588, 'weight': 0.8}, {'end': 1113.474, 'start': 1009.104, 'weight': 0.833}, {'end': 1432.227, 'start': 1389.895, 'weight': 0.794}], 'summary': 'Covers python programming lecture, hash tables, dictionary methods, data organization, efficient file reading, and word count exercises, emphasizing practical applications and efficiency, with specific examples and quantifiable data.', 'chapters': [{'end': 27.023, 'segs': [{'end': 34.03, 'src': 'embed', 'start': 0.421, 'weight': 0, 'content': [{'end': 0.641, 'text': 'All right.', 'start': 0.421, 'duration': 0.22}, {'end': 1.061, 'text': 'Hey, everybody.', 'start': 0.661, 'duration': 0.4}, {'end': 2.442, 'text': 'All right.', 'start': 1.081, 'duration': 1.361}, {'end': 2.922, 'text': 'Sorry to interrupt you.', 'start': 2.462, 'duration': 0.46}, {'end': 4.503, 'text': 'I see a lot of people working away on list one.', 'start': 2.942, 'duration': 1.561}, {'end': 7.024, 'text': "It's not a requirement that you finish, like, all the problems on list one.", 'start': 4.663, 'duration': 2.361}, {'end': 8.724, 'text': "I'm just hoping that people can get, like, some of them.", 'start': 7.044, 'duration': 1.68}, {'end': 15.247, 'text': "What I'd like to do is I want to do another quick lecture section, and then I want to break out time for, you know, a nice long exercise at the end.", 'start': 9.425, 'duration': 5.822}, {'end': 19.969, 'text': "You're welcome to keep working on the list problems if you want, but this last exercise, once we have file reading,", 'start': 15.267, 'duration': 4.702}, {'end': 22.31, 'text': "then it can begin to look like a real program and it's going to involve.", 'start': 19.969, 'duration': 2.341}, {'end': 24.731, 'text': "it's going to sum up all the material we've talked about, lists and strings and all that stuff.", 'start': 22.31, 'duration': 2.421}, {'end': 25.191, 'text': 'Put it all together.', 'start': 24.751, 'duration': 0.44}, {'end': 27.023, 'text': "And that'll be the last thing for today.", 'start': 25.982, 'duration': 1.041}, {'end': 34.03, 'text': 'So the last data structure I want to show you is the hash table, or also called a dictionary.', 'start': 28.304, 'duration': 5.726}], 'summary': 'Lecture on coding exercises with emphasis on file reading and data structures like lists and dictionaries.', 'duration': 33.609, 'max_score': 0.421, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg421.jpg'}], 'start': 0.421, 'title': 'Python programming lecture and exercise', 'summary': 'Covers the python programming lecture, emphasizing that completion of all problems in list one is not mandatory and ends with a long exercise integrating file reading, lists, and strings.', 'chapters': [{'end': 27.023, 'start': 0.421, 'title': 'Python programming lecture and exercise', 'summary': 'Covers the python programming lecture, emphasizing that completion of all problems in list one is not mandatory and ending with a long exercise integrating file reading, lists, and strings.', 'duration': 26.602, 'highlights': ['The last exercise will integrate file reading, lists, and strings, summing up all the material discussed.', 'Completion of all problems on list one is not mandatory, but participants are encouraged to attempt some of them.', 'A quick lecture section will be followed by a long exercise at the end.']}], 'duration': 26.602, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg421.jpg', 'highlights': ['The last exercise integrates file reading, lists, and strings', 'Completion of all problems on list one is not mandatory', 'A quick lecture section will be followed by a long exercise']}, {'end': 470.405, 'segs': [{'end': 79.961, 'src': 'embed', 'start': 52.559, 'weight': 1, 'content': [{'end': 56.321, 'text': "And the way the dictionary works and I've got a little piece of art there from the handout at the top is.", 'start': 52.559, 'duration': 3.762}, {'end': 60.442, 'text': "you can think of it as it's set to contain key value bindings.", 'start': 56.321, 'duration': 4.121}, {'end': 63.224, 'text': 'For each key, it can look up that value very quickly.', 'start': 60.462, 'duration': 2.762}, {'end': 71.878, 'text': "So the way that works in Python is I'll say under the key A, I would like to store the string alpha.", 'start': 64.164, 'duration': 7.714}, {'end': 77.24, 'text': "And under the string O, I'm just going to make the same example I have in that little picture there.", 'start': 72.598, 'duration': 4.642}, {'end': 79.961, 'text': "I'll store omega.", 'start': 77.26, 'duration': 2.701}], 'summary': 'Python dictionary stores key-value bindings for quick lookups.', 'duration': 27.402, 'max_score': 52.559, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg52559.jpg'}, {'end': 116.04, 'src': 'embed', 'start': 94.025, 'weight': 0, 'content': [{'end': 103.613, 'text': 'And then later on, when you try and retrieve by key, this is the one thing that hash tables are fast at, it can retrieve by a key in constant time.', 'start': 94.025, 'duration': 9.588}, {'end': 104.994, 'text': "It's just as fast as you can imagine.", 'start': 103.713, 'duration': 1.281}, {'end': 106.656, 'text': "It's very quick at key retrieval.", 'start': 105.014, 'duration': 1.642}, {'end': 111.518, 'text': 'So for example, if I say, OK, dictionary, and in Python, the way it works is we just use the square brackets.', 'start': 107.276, 'duration': 4.242}, {'end': 116.04, 'text': 'When I use the square bracket on the left, I was storing a value in.', 'start': 111.978, 'duration': 4.062}], 'summary': 'Hash tables are fast at retrieving by key, in constant time.', 'duration': 22.015, 'max_score': 94.025, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg94025.jpg'}, {'end': 184.478, 'src': 'embed', 'start': 155.307, 'weight': 8, 'content': [{'end': 159.49, 'text': 'So let me show you a few more features you can do with dictionary.', 'start': 155.307, 'duration': 4.183}, {'end': 161.751, 'text': 'So obviously, you can store stuff in.', 'start': 159.51, 'duration': 2.241}, {'end': 163.132, 'text': 'You can use the square to get stuff out.', 'start': 161.771, 'duration': 1.361}, {'end': 169.415, 'text': 'If I refer to a key that is not in there, I say all right dictionary, what do you have for key value x?', 'start': 164.152, 'duration': 5.263}, {'end': 173.071, 'text': 'What I get is actually an error, a key error.', 'start': 170.609, 'duration': 2.462}, {'end': 174.532, 'text': "So that's a little unpleasant.", 'start': 173.111, 'duration': 1.421}, {'end': 178.234, 'text': 'I think Python is trying to be sort of consistent with the list here.', 'start': 175.392, 'duration': 2.842}, {'end': 184.478, 'text': 'That if I said list square bracket like a thousand and there is no thousand, you know, it would have given an error.', 'start': 178.734, 'duration': 5.744}], 'summary': 'Demonstrating dictionary features for storing and retrieving items, handling key errors in python.', 'duration': 29.171, 'max_score': 155.307, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg155307.jpg'}, {'end': 238.077, 'src': 'embed', 'start': 190.762, 'weight': 6, 'content': [{'end': 192.203, 'text': "And if you refer to something that's not there, it's an error.", 'start': 190.762, 'duration': 1.441}, {'end': 194.105, 'text': "Fortunately, there's an alternative.", 'start': 192.744, 'duration': 1.361}, {'end': 197.947, 'text': "There's a dot get method on the dictionary.", 'start': 195.005, 'duration': 2.942}, {'end': 208.695, 'text': "And so if you do dot get, In the simplest form, what it does is it returns the value none if it's not in there, and otherwise it returns the value.", 'start': 198.608, 'duration': 10.087}, {'end': 215.12, 'text': 'So if I say dot get of A, then I get alpha, but of X, then I just get back nothing.', 'start': 208.735, 'duration': 6.385}, {'end': 216.661, 'text': 'It happens in the interpreter.', 'start': 215.4, 'duration': 1.261}, {'end': 218.162, 'text': 'None is sort of a special case.', 'start': 216.741, 'duration': 1.421}, {'end': 219.503, 'text': 'It just prints nothing and just comes back.', 'start': 218.202, 'duration': 1.301}, {'end': 225.174, 'text': 'So, if you want to distinguish, you know, if you want to, if you care whether or not thing is in there,', 'start': 220.713, 'duration': 4.461}, {'end': 226.434, 'text': "then you could use get and you're more protected.", 'start': 225.174, 'duration': 1.26}, {'end': 236.177, 'text': 'How do you suppose you test if a value is in a dictionary? Someone say? Something I wrote I think over there.', 'start': 227.135, 'duration': 9.042}, {'end': 238.077, 'text': 'All right.', 'start': 236.197, 'duration': 1.88}], 'summary': "Using the dot get method on a dictionary returns 'none' if the value is not there, otherwise it returns the value.", 'duration': 47.315, 'max_score': 190.762, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg190762.jpg'}, {'end': 310.093, 'src': 'embed', 'start': 282.186, 'weight': 5, 'content': [{'end': 287.654, 'text': 'So, the simplest way to do that is the dictionary has a method called .', 'start': 282.186, 'duration': 5.468}, {'end': 292.16, 'text': 'keys And what that does is it returns a list of just the keys.', 'start': 287.654, 'duration': 4.506}, {'end': 297.869, 'text': "There's also a list of, oh, notice the keys are in kind of random order.", 'start': 293.167, 'duration': 4.702}, {'end': 302.991, 'text': 'Now, in this case, I guess they appear to be in alphabetical order, but as the dictionary gets bigger and bigger,', 'start': 298.829, 'duration': 4.162}, {'end': 304.131, 'text': 'these will be in kind of a random order.', 'start': 302.991, 'duration': 1.14}, {'end': 310.093, 'text': 'This is the hashing strategy that the dictionary uses causes the keys to be in a scrambled order.', 'start': 304.171, 'duration': 5.922}], 'summary': "The dictionary's keys method returns a list of keys, which may appear in a random order due to the hashing strategy.", 'duration': 27.907, 'max_score': 282.186, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg282186.jpg'}, {'end': 362.192, 'src': 'embed', 'start': 324.93, 'weight': 4, 'content': [{'end': 327.213, 'text': "Oops, what's the problem there? Oops, I spelled it wrong.", 'start': 324.93, 'duration': 2.283}, {'end': 331.945, 'text': 'So this just pulls out the linear list of values.', 'start': 329.284, 'duration': 2.661}, {'end': 336.326, 'text': "And it's actually, it's in a kind of a random order, but it's in the same random order that the .", 'start': 331.985, 'duration': 4.341}, {'end': 336.806, 'text': 'keys was.', 'start': 336.326, 'duration': 0.48}, {'end': 342.007, 'text': "So I'm going to show you what I would regard as kind of the most common case of looping over a dictionary.", 'start': 336.826, 'duration': 5.181}, {'end': 343.427, 'text': "You've built the dictionary, it's got all this.", 'start': 342.027, 'duration': 1.4}, {'end': 348.028, 'text': 'you know social security numbers or URLs or whatever in it, and now you want to loop over and look at them.', 'start': 343.427, 'duration': 4.601}, {'end': 350.109, 'text': 'I would write it this way.', 'start': 349.389, 'duration': 0.72}, {'end': 362.192, 'text': "I'd say well for k in dictionary.keys. So what that means is go to the dictionary, pull out the linear list of keys and now I want to loop over that.", 'start': 350.449, 'duration': 11.743}], 'summary': 'Demonstration of looping over a dictionary using linear list of keys.', 'duration': 37.262, 'max_score': 324.93, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg324930.jpg'}, {'end': 459.56, 'src': 'embed', 'start': 431.546, 'weight': 3, 'content': [{'end': 436.79, 'text': 'items does is, rather than just pulling out the key or just pulling out the value,', 'start': 431.546, 'duration': 5.244}, {'end': 440.693, 'text': 'it pulls them both out simultaneously and it puts each one in a tuple size two.', 'start': 436.79, 'duration': 3.903}, {'end': 443.935, 'text': "So what you're seeing here is a list of tuples.", 'start': 441.754, 'duration': 2.181}, {'end': 450.981, 'text': 'each tuple is length two and each tuple represents one, what I would call a binding from the dictionary.', 'start': 443.935, 'duration': 7.046}, {'end': 459.56, 'text': 'And so what you could do is you could, if you really want to just get the key and value all in one step, then you could use .', 'start': 452.242, 'duration': 7.318}], 'summary': "Python's items method pulls key-value pairs into tuples.", 'duration': 28.014, 'max_score': 431.546, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg431546.jpg'}], 'start': 28.304, 'title': 'Python hash tables and dictionary methods', 'summary': 'Explains the concept of hash tables in python, emphasizing quick key lookup and limitations, and discusses dictionary methods like get, keys, values, and items, along with their practical applications and benefits, including the ability to organize data and perform looping operations.', 'chapters': [{'end': 190.342, 'start': 28.304, 'title': 'Hash table in python', 'summary': 'Explains the concept of a hash table, also known as a dictionary, and its efficiency in key-value pair retrieval in python, with a focus on quick key lookup and its limitations in handling non-existent keys.', 'duration': 162.038, 'highlights': ['Hash tables, also known as dictionaries in Python, are efficient data structures for quick key-value pair retrieval, with constant time lookup for a particular key, providing fast key retrieval.', 'The delimiter character for a dictionary in Python is the curly brace, and it allows for easy creation and manipulation of key-value pairs.', 'Python dictionaries are fast at key retrieval, capable of retrieving a particular key in just a few cycles on the machine, even with a large number of keys.', 'Attempting to retrieve a key that does not exist in the dictionary results in a key error, indicating a limitation in handling non-existent keys, similar to the behavior of lists in Python.']}, {'end': 470.405, 'start': 190.762, 'title': 'Dictionary methods and looping', 'summary': "Discusses the usage of dictionary methods such as get, keys, values, and items, emphasizing their practical applications and benefits, including the ability to organize data and perform looping operations. it also highlights the distinction between 'in' and 'get' methods for testing the presence of a value in a dictionary.", 'duration': 279.643, 'highlights': ["The dot get method returns 'none' if the value is not present in the dictionary, otherwise it returns the value, providing a practical alternative for error handling.", "The 'in' method is used to test if a value is present in the dictionary, offering a simple way to check for the existence of a specific key.", 'The .keys method returns a list of keys from the dictionary, which can be useful for organizing and accessing the key-value pairs.', 'The .values method pulls out a linear list of values from the dictionary, enabling easy access to the stored values.', 'The .items method retrieves key-value pairs as tuples, offering a convenient way to access both keys and values simultaneously during looping operations.']}], 'duration': 442.101, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg28304.jpg', 'highlights': ['Hash tables in Python provide constant time lookup for key retrieval', 'Python dictionaries allow easy creation and manipulation of key-value pairs', 'Python dictionaries are fast at key retrieval even with a large number of keys', 'The .items method retrieves key-value pairs as tuples for looping operations', 'The .values method pulls out a linear list of values from the dictionary', 'The .keys method returns a list of keys from the dictionary', "The dot get method returns 'none' if the value is not present in the dictionary", "The 'in' method is used to test if a value is present in the dictionary", 'Attempting to retrieve a non-existent key in the dictionary results in a key error']}, {'end': 1050.098, 'segs': [{'end': 527.547, 'src': 'embed', 'start': 501.181, 'weight': 0, 'content': [{'end': 506.546, 'text': "And in a sense, the Apache log file there, it's just random, right? This IP address requests something and then this one and then that one, whatever.", 'start': 501.181, 'duration': 5.365}, {'end': 507.627, 'text': "It's all just kind of jumbled together.", 'start': 506.586, 'duration': 1.041}, {'end': 516.014, 'text': 'A very common form of the use of the dictionary in solving a problem is that it takes incoherent data and it makes it coherent.', 'start': 508.307, 'duration': 7.707}, {'end': 516.934, 'text': 'It organizes it.', 'start': 516.094, 'duration': 0.84}, {'end': 523.741, 'text': 'So, for example, suppose I wanted to count how many times each IP address had been hitting my server by looking at this log file.', 'start': 517.434, 'duration': 6.307}, {'end': 527.547, 'text': "What I could do is I'd say, OK, I'm going to rip through the entire file, which I'll show you in a second.", 'start': 524.341, 'duration': 3.206}], 'summary': 'Using a dictionary to organize incoherent apache log file data for ip address hit counts.', 'duration': 26.366, 'max_score': 501.181, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg501181.jpg'}, {'end': 599.405, 'src': 'embed', 'start': 566.895, 'weight': 1, 'content': [{'end': 569.376, 'text': 'the dictionary is like hands down.', 'start': 566.895, 'duration': 2.481}, {'end': 569.997, 'text': 'the good way to do that.', 'start': 569.376, 'duration': 0.621}, {'end': 576.519, 'text': "And it relies on this fact that it's very fast at this one operation, which is given any random key, it can look up that value very, very quickly.", 'start': 570.057, 'duration': 6.462}, {'end': 583.747, 'text': 'Now, stepping even farther outside of myself, Google really runs as a big hash table.', 'start': 577.68, 'duration': 6.067}, {'end': 585.849, 'text': "And that's basically what it is.", 'start': 584.307, 'duration': 1.542}, {'end': 588.192, 'text': "It's a big hash table by word.", 'start': 586.41, 'duration': 1.782}, {'end': 592.477, 'text': 'And each word kind of points to a list of URLs or scores or something.', 'start': 589.113, 'duration': 3.364}, {'end': 599.405, 'text': "So as a user, when you type in a word, Britney Spears, That's two words, I guess.", 'start': 592.757, 'duration': 6.648}], 'summary': "Google's system operates as a fast, efficient hash table for quick value lookups.", 'duration': 32.51, 'max_score': 566.895, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg566895.jpg'}, {'end': 661.433, 'src': 'embed', 'start': 632.635, 'weight': 2, 'content': [{'end': 634.155, 'text': 'And in fact dictionaries are.', 'start': 632.635, 'duration': 1.52}, {'end': 640.396, 'text': "I mean you can sort of see the subtext I'm telling you is dictionaries are an extremely useful and powerful construct,", 'start': 634.155, 'duration': 6.241}, {'end': 642.137, 'text': "and so I'm going to want to push you to use them.", 'start': 640.396, 'duration': 1.741}, {'end': 643.457, 'text': "Like, it's a good thing to get practice with.", 'start': 642.157, 'duration': 1.3}, {'end': 649.221, 'text': 'All right, so let me show you the last thing, which is files.', 'start': 644.597, 'duration': 4.624}, {'end': 655.548, 'text': "And I think I'm going to go back to editing hello.py for this.", 'start': 650.503, 'duration': 5.045}, {'end': 661.433, 'text': "I'm going to show you some file stuff here.", 'start': 655.588, 'duration': 5.845}], 'summary': 'Dictionaries are useful and powerful, practice with them. also, files are important for programming.', 'duration': 28.798, 'max_score': 632.635, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg632635.jpg'}, {'end': 863.484, 'src': 'heatmap', 'start': 655.588, 'weight': 6, 'content': [{'end': 661.433, 'text': "I'm going to show you some file stuff here.", 'start': 655.588, 'duration': 5.845}, {'end': 669.421, 'text': "All right, so this is just, you know, I'm going to, in Unix there's this utility cat.", 'start': 661.573, 'duration': 7.848}, {'end': 676.562, 'text': 'And what it does is it just, you know, prints out the contents of a file.', 'start': 672.119, 'duration': 4.443}, {'end': 680.344, 'text': "So, I'm just going to go ahead and kind of recreate cat in Python just to kind of show you how to open files.", 'start': 676.762, 'duration': 3.582}, {'end': 684.146, 'text': "So, let's say this thing takes a file name.", 'start': 681.784, 'duration': 2.362}, {'end': 686.707, 'text': "I'm going to write a function called cat and it takes a file name argument.", 'start': 684.186, 'duration': 2.521}, {'end': 689.189, 'text': 'And what I want to do is just print the contents of that file out.', 'start': 687.007, 'duration': 2.182}, {'end': 695.172, 'text': "So, the way to do this is there's a built-in called open.", 'start': 691.11, 'duration': 4.062}, {'end': 700.892, 'text': 'And its first argument is a file name and the second argument to this kind of resembles other languages.', 'start': 696.431, 'duration': 4.461}, {'end': 707.775, 'text': 'I can specify an R here to mean, oh, I want to open this for reading or I could specify a W to mean I want to open it for writing or whatever.', 'start': 702.033, 'duration': 5.742}, {'end': 709.855, 'text': "In this case, we'll just, we'll open this for reading.", 'start': 707.795, 'duration': 2.06}, {'end': 715.737, 'text': "And there's actually a variant if you put an RU there, it opens it in a way where it's going to.", 'start': 710.796, 'duration': 4.941}, {'end': 718.898, 'text': "it'll ignore DOS line endings versus Unix line endings or whatever.", 'start': 715.737, 'duration': 3.161}, {'end': 720.399, 'text': "It'll kind of fix that under the hood, so that's nice.", 'start': 718.918, 'duration': 1.481}, {'end': 730.721, 'text': "So probably the simplest way to deal with let's say there's a text file to deal with all the lines in a file is you can actually write a for loop over a file,", 'start': 722.559, 'duration': 8.162}, {'end': 731.602, 'text': 'sort of like it was a list.', 'start': 730.721, 'duration': 0.881}, {'end': 737.083, 'text': 'So I can say for line in F.', 'start': 732.202, 'duration': 4.881}, {'end': 742.665, 'text': 'So I loop over F and what it does is it actually reads the file in line by line and just processes one line at a time.', 'start': 737.083, 'duration': 5.582}, {'end': 750.287, 'text': "So if I were to say print line, I want to just echo the file, so I'll just print each line.", 'start': 743.345, 'duration': 6.942}, {'end': 754.071, 'text': "And then here, I'll fix up my main to call this thing.", 'start': 751.109, 'duration': 2.962}, {'end': 761.577, 'text': "So main just takes whatever command line argument I have here, and it's just going to call cat and just say, print this out.", 'start': 756.393, 'duration': 5.184}, {'end': 771.365, 'text': "So I'm here, right? OK, so let's see.", 'start': 762.678, 'duration': 8.687}, {'end': 775.648, 'text': "In day one, so I've got this file, a small.txt.", 'start': 771.485, 'duration': 4.163}, {'end': 777.71, 'text': "I'm going to take that up here.", 'start': 775.688, 'duration': 2.022}, {'end': 782.349, 'text': "Okay, so if we look at what's in small.txt, it's this beautiful poem I wrote for the class.", 'start': 778.868, 'duration': 3.481}, {'end': 785.21, 'text': 'All right.', 'start': 783.53, 'duration': 1.68}, {'end': 794.914, 'text': "so now, if I say hello.py of small.txt, what it's doing is it's so I open that file, it's reading it and it's printing it,", 'start': 785.21, 'duration': 9.704}, {'end': 798.435, 'text': "but I'm getting this kind of line doubling, not improving my poem.", 'start': 794.914, 'duration': 3.521}, {'end': 804.689, 'text': 'So the problem is this line string, it includes the new line at the end.', 'start': 799.864, 'duration': 4.825}, {'end': 808.212, 'text': "And then when I print it, I'm kind of putting another new line there.", 'start': 805.529, 'duration': 2.683}, {'end': 816.72, 'text': "So to fix this, Python obscure syntax, if you put, if there's a trailing comma at the end, that inhibits that last new line.", 'start': 808.912, 'duration': 7.808}, {'end': 818.782, 'text': "So I'll save that.", 'start': 817.841, 'duration': 0.941}, {'end': 821.204, 'text': "I'll just run it again.", 'start': 818.802, 'duration': 2.402}, {'end': 822.565, 'text': 'Excellent Okay.', 'start': 821.984, 'duration': 0.581}, {'end': 825.915, 'text': 'All right, so that is one way to read a file.', 'start': 823.854, 'duration': 2.061}, {'end': 831.339, 'text': 'You open it into this thing F, which is kind of a file handle kind of thing, and then you just loop over it.', 'start': 826.356, 'duration': 4.983}, {'end': 836.543, 'text': 'This technique where you loop over line by line, it has this one virtue.', 'start': 831.719, 'duration': 4.824}, {'end': 838.705, 'text': 'sort of going back to my Apache.', 'start': 837.765, 'duration': 0.94}, {'end': 847.009, 'text': "I could have an Apache log that's like 47 gigabytes of just text, and this loop will run through it, but it will not require 47 gigabytes of RAM.", 'start': 838.946, 'duration': 8.063}, {'end': 851.651, 'text': "This uses a tiny bit of RAM because it deals with each line independently, and that's an efficient case.", 'start': 847.269, 'duration': 4.382}, {'end': 856.113, 'text': 'So if you can go line by line, this is the efficient way to do it.', 'start': 851.951, 'duration': 4.162}, {'end': 859.615, 'text': "Also, just for completeness, at the end, there's a .", 'start': 856.293, 'duration': 3.322}, {'end': 863.484, 'text': 'close I should have done it, you know, close the file, just to be polite.', 'start': 859.615, 'duration': 3.869}], 'summary': 'Demonstrates file handling in python, including opening, reading, and looping over a file, with consideration for efficiency and closing the file.', 'duration': 57.955, 'max_score': 655.588, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg655588.jpg'}, {'end': 930.686, 'src': 'embed', 'start': 903.042, 'weight': 4, 'content': [{'end': 908.108, 'text': "You just have to keep in your head what's a file name, what's a file, what's a string, what's a list.", 'start': 903.042, 'duration': 5.066}, {'end': 910.892, 'text': 'Now, there is something you can do about this.', 'start': 908.689, 'duration': 2.203}, {'end': 915.097, 'text': 'The one thing you can do, the one thing you get in Python is your variable names.', 'start': 911.613, 'duration': 3.484}, {'end': 921.378, 'text': 'And you knew, you were taught or whatever, you knew, oh yeah, having good variable names is kind of a good idea.', 'start': 915.993, 'duration': 5.385}, {'end': 924.921, 'text': "But in Python, it's ten times more important.", 'start': 921.898, 'duration': 3.023}, {'end': 930.686, 'text': "So I want to point out in my little garbagey example here now, when I'm typing stuff in the interpreter, a lot of times I use one variable names,", 'start': 925.341, 'duration': 5.345}], 'summary': 'In python, using good variable names is ten times more important.', 'duration': 27.644, 'max_score': 903.042, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg903042.jpg'}, {'end': 1009.704, 'src': 'embed', 'start': 975.518, 'weight': 3, 'content': [{'end': 981.461, 'text': "And I'll tell you, it pays off very well to be conscious of giving your variables good names of like.", 'start': 975.518, 'duration': 5.943}, {'end': 982.041, 'text': 'what is that??', 'start': 981.461, 'duration': 0.58}, {'end': 983.181, 'text': 'Is that a string??', 'start': 982.401, 'duration': 0.78}, {'end': 983.781, 'text': 'Is that a list??', 'start': 983.281, 'duration': 0.5}, {'end': 984.402, 'text': 'Is that a dictionary??', 'start': 983.801, 'duration': 0.601}, {'end': 984.662, 'text': 'Whatever?', 'start': 984.442, 'duration': 0.22}, {'end': 987.443, 'text': 'And certainly in my solutions, whatever, you know, I fall back.', 'start': 985.402, 'duration': 2.041}, {'end': 988.524, 'text': "I mean, it's just good style anyway.", 'start': 987.484, 'duration': 1.04}, {'end': 992.087, 'text': "But in Python, it happens to pay off especially well because you've got so little else going on.", 'start': 988.544, 'duration': 3.543}, {'end': 992.467, 'text': 'All right.', 'start': 992.287, 'duration': 0.18}, {'end': 994.888, 'text': 'So, on our bigger exercise today, this will certainly come up.', 'start': 992.687, 'duration': 2.201}, {'end': 1000.012, 'text': 'The other way that this comes up is, whenever I have a list of things, I will try and give it a variable name,', 'start': 995.269, 'duration': 4.743}, {'end': 1004.815, 'text': 'ending in S words or lines or something like that to sort of cue me like all right.', 'start': 1000.012, 'duration': 4.803}, {'end': 1005.575, 'text': "that's the list of things.", 'start': 1004.815, 'duration': 0.76}, {'end': 1007.897, 'text': 'Okay End of editorial.', 'start': 1006.616, 'duration': 1.281}, {'end': 1009.704, 'text': "It's actually good advice.", 'start': 1009.104, 'duration': 0.6}], 'summary': 'Conscious naming of variables pays off well, especially in python, where little else is happening. giving lists variable names ending in s, words, or lines is helpful.', 'duration': 34.186, 'max_score': 975.518, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg975518.jpg'}], 'start': 473.447, 'title': 'Organizing data, efficient file reading, and variable naming in python', 'summary': "Explains the power of dictionaries in organizing data, with examples of counting ip addresses and google's analogy, discusses efficient file reading with python using a for loop, and emphasizes the importance of descriptive variable naming to avoid confusion and errors in python, with specific examples of file handling and data type tracking.", 'chapters': [{'end': 718.898, 'start': 473.447, 'title': 'The power of dictionaries in organizing data', 'summary': 'Explains how dictionaries can efficiently organize and associate incoherent data, as seen in the example of counting ip addresses in apache log files and the analogy of google running as a large hash table. dictionaries are highlighted as an extremely useful and powerful construct.', 'duration': 245.451, 'highlights': ['Dictionaries efficiently organize incoherent data, as demonstrated by the example of counting IP addresses in Apache log files.', 'The analogy of Google running as a large hash table emphasizes the powerful and efficient nature of dictionaries in organizing and associating data.', 'The chapter stresses the extreme usefulness and power of dictionaries, encouraging the audience to practice using them.']}, {'end': 882.342, 'start': 718.918, 'title': 'Efficient file reading with python', 'summary': 'Discusses a python script for reading a text file line by line using a for loop, highlighting the efficiency of processing large files without consuming excessive ram and the importance of closing the file handle at the end.', 'duration': 163.424, 'highlights': ['The efficiency of processing large files without consuming excessive RAM', 'Importance of closing the file handle at the end', 'Syntax for inhibiting the last new line in Python']}, {'end': 1050.098, 'start': 884.181, 'title': 'Importance of variable naming in python', 'summary': 'Discusses the importance of naming variables in python, emphasizing the need for clear, descriptive variable names to avoid confusion and errors, and highlights the significance of using variable names to keep track of data types and progression, with a specific example of utilizing variable naming in file handling and reading lines from a file in python.', 'duration': 165.917, 'highlights': ['In Python, there are no cues about variable types, making it essential to keep track of data types through variable naming (e.g., file name, file, string, list) to avoid confusion and errors.', 'Using clear and descriptive variable names in Python is crucial, as it helps in keeping track of variable types and reduces the chances of errors, with good variable naming being ten times more important in Python.', "Variable naming is particularly important in Python to avoid getting 'off by one' and losing track of the progression of data types (e.g., file name, file, line of text, word), as variable names are the only cues available for tracking data progression.", 'The significance of conscious and descriptive variable naming in Python is highlighted, particularly in debugging basic Python programs, where good variable names are crucial and can lead to effective solutions.', "When working with a list of items in Python, it is recommended to use a variable name ending in 'S' (e.g., words, lines) to indicate that it is a list of things."]}], 'duration': 576.651, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg473447.jpg', 'highlights': ['Dictionaries efficiently organize incoherent data, as demonstrated by the example of counting IP addresses in Apache log files.', 'The analogy of Google running as a large hash table emphasizes the powerful and efficient nature of dictionaries in organizing and associating data.', 'The chapter stresses the extreme usefulness and power of dictionaries, encouraging the audience to practice using them.', 'The significance of conscious and descriptive variable naming in Python is highlighted, particularly in debugging basic Python programs, where good variable names are crucial and can lead to effective solutions.', 'Using clear and descriptive variable names in Python is crucial, as it helps in keeping track of variable types and reduces the chances of errors, with good variable naming being ten times more important in Python.', 'In Python, there are no cues about variable types, making it essential to keep track of data types through variable naming (e.g., file name, file, string, list) to avoid confusion and errors.', 'The efficiency of processing large files without consuming excessive RAM', 'Importance of closing the file handle at the end', 'Syntax for inhibiting the last new line in Python', "When working with a list of items in Python, it is recommended to use a variable name ending in 'S' (e.g., words, lines) to indicate that it is a list of things."]}, {'end': 1286.762, 'segs': [{'end': 1094.1, 'src': 'embed', 'start': 1050.518, 'weight': 0, 'content': [{'end': 1052.879, 'text': 'So now you could loop over that list to do something or whatever.', 'start': 1050.518, 'duration': 2.361}, {'end': 1060.022, 'text': 'So, if you had a file with like, you know, 10, 000 something others that you want to process as a list, you know, this is one easy way.', 'start': 1054.22, 'duration': 5.802}, {'end': 1061.043, 'text': 'You just pull it into RAM in one step.', 'start': 1060.042, 'duration': 1.001}, {'end': 1066.664, 'text': 'Notice if the thing is 28 gigs of data, now this does take at least 28 gigs of RAM to store.', 'start': 1062.223, 'duration': 4.441}, {'end': 1068.385, 'text': 'Like I really am just storing the whole thing around.', 'start': 1066.845, 'duration': 1.54}, {'end': 1071.126, 'text': 'But on the other hand, I get very, you know, convenient access to it.', 'start': 1068.625, 'duration': 2.501}, {'end': 1079.563, 'text': "My absolute favorite, I know you've been very curious, what is my favorite Python file primitive.", 'start': 1072.426, 'duration': 7.137}, {'end': 1083.968, 'text': "Oops And it's just, there's this one just called read.", 'start': 1079.643, 'duration': 4.325}, {'end': 1088.533, 'text': 'And what it does is it reads the entire file into one string.', 'start': 1084.929, 'duration': 3.604}, {'end': 1094.1, 'text': "And I know that's it, but for some problems that is just so convenient.", 'start': 1090.996, 'duration': 3.104}], 'summary': 'Python provides an easy way to process large files by reading them into ram in one step, but it requires significant memory.', 'duration': 43.582, 'max_score': 1050.518, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1050518.jpg'}, {'end': 1170.715, 'src': 'embed', 'start': 1140.048, 'weight': 4, 'content': [{'end': 1142.249, 'text': 'These are the last two elements that you needed to now write.', 'start': 1140.048, 'duration': 2.201}, {'end': 1147.951, 'text': "It's kind of an inflection point where like with all the stuff I've showed you now, you can write just like real Python programs.", 'start': 1142.609, 'duration': 5.342}, {'end': 1150.573, 'text': "And so that's what our last exercise is going to look like.", 'start': 1147.991, 'duration': 2.582}, {'end': 1152.694, 'text': 'I already gave you the advice about variable names.', 'start': 1151.213, 'duration': 1.481}, {'end': 1155.175, 'text': 'One other piece of advice I should give you.', 'start': 1153.714, 'duration': 1.461}, {'end': 1158.556, 'text': "I'm about to demo some larger programs for you that I want you to implement.", 'start': 1155.755, 'duration': 2.801}, {'end': 1170.715, 'text': "It is the, sometimes, at Stanford, right, if I'm talking to some 17-year-old, what they will do is they'll type in the entire program.", 'start': 1161.058, 'duration': 9.657}], 'summary': 'Learn to write real python programs with proper variable names and implement larger programs', 'duration': 30.667, 'max_score': 1140.048, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1140048.jpg'}, {'end': 1249.115, 'src': 'embed', 'start': 1223.356, 'weight': 1, 'content': [{'end': 1228.518, 'text': "And so just have the program print what your kind of next goal is and keep iterating it until it's printing the right thing.", 'start': 1223.356, 'duration': 5.162}, {'end': 1234.601, 'text': 'And Python, because Python is very easy to edit and its built-in printing facility is actually quite good, right?', 'start': 1229.058, 'duration': 5.543}, {'end': 1237.062, 'text': 'You can print a dictionary, you can print a list, all that stuff.', 'start': 1234.621, 'duration': 2.441}, {'end': 1238.142, 'text': "there's no code in your card required.", 'start': 1237.062, 'duration': 1.08}, {'end': 1241.003, 'text': "It just prints, it just, it'll dump something kind of reasonable to the console.", 'start': 1238.162, 'duration': 2.841}, {'end': 1247.046, 'text': "And so you can use that to kind of iterate very tightly and certainly as I walk around answering questions, this is the same thing I'll do.", 'start': 1241.724, 'duration': 5.322}, {'end': 1249.115, 'text': "So, that's my way.", 'start': 1247.934, 'duration': 1.181}], 'summary': 'Iterate program goal in python, leveraging built-in printing for efficient iteration.', 'duration': 25.759, 'max_score': 1223.356, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1223356.jpg'}, {'end': 1275.336, 'src': 'embed', 'start': 1251.315, 'weight': 3, 'content': [{'end': 1257.778, 'text': "it's kind of nice if you print what your data structure has, kind of as step end of solving this thing, seeing the pixels of like.", 'start': 1251.315, 'duration': 6.463}, {'end': 1261.319, 'text': 'oh, I have a list of strings or whatever can help your imagination think of like.', 'start': 1257.778, 'duration': 3.541}, {'end': 1262.42, 'text': "okay, well, what's my next step?", 'start': 1261.319, 'duration': 1.101}, {'end': 1263.86, 'text': 'Oh, now I need to make a list.', 'start': 1262.5, 'duration': 1.36}, {'end': 1265.361, 'text': 'you know a dictionary or something?', 'start': 1263.86, 'duration': 1.501}, {'end': 1267.902, 'text': "And so, it's nice to be able to just see your data structure right there.", 'start': 1265.961, 'duration': 1.941}, {'end': 1270.983, 'text': 'And I guess more broadly.', 'start': 1268.902, 'duration': 2.081}, {'end': 1275.336, 'text': 'you know why is it the Python programmers get in this zone of like?', 'start': 1272.574, 'duration': 2.762}], 'summary': 'Python programmers value visualizing data structures for problem-solving.', 'duration': 24.021, 'max_score': 1251.315, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1251315.jpg'}], 'start': 1050.518, 'title': 'Python programming techniques', 'summary': 'Covers python file handling basics, including reading files into ram, accessing and iterating through lines. it also emphasizes incremental programming in python for higher productivity, suggesting printing the current state of the program.', 'chapters': [{'end': 1177.742, 'start': 1050.518, 'title': 'Python file handling basics', 'summary': 'Covers python file handling basics, including reading an entire file into ram, accessing it conveniently, and iterating through lines, enabling the writing of real python programs with the demonstrated techniques.', 'duration': 127.224, 'highlights': ['Reading entire file into RAM allows convenient access but consumes significant memory', 'Reading entire file into one string is phenomenally convenient for some operations', 'Iterating through lines and using variable names enable writing real Python programs']}, {'end': 1286.762, 'start': 1178.042, 'title': 'Incremental python programming', 'summary': 'Emphasizes the importance of incremental programming in python, suggesting to print the current state of the program to iterate tightly and efficiently, leading to higher productivity in python programming.', 'duration': 108.72, 'highlights': ['The importance of incremental programming in Python, suggesting to print the current state of the program to iterate tightly and efficiently, leading to higher productivity in Python programming.', "Emphasizing the benefits of Python's easy editing and built-in printing facility, allowing for quick iteration and solving problems efficiently.", 'Highlighting the significance of understanding and visualizing the data structure, using it to plan the next steps in the program.']}], 'duration': 236.244, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1050518.jpg', 'highlights': ['Reading entire file into one string is phenomenally convenient for some operations', 'The importance of incremental programming in Python, suggesting to print the current state of the program to iterate tightly and efficiently, leading to higher productivity in Python programming.', "Emphasizing the benefits of Python's easy editing and built-in printing facility, allowing for quick iteration and solving problems efficiently.", 'Highlighting the significance of understanding and visualizing the data structure, using it to plan the next steps in the program.', 'Iterating through lines and using variable names enable writing real Python programs', 'Reading entire file into RAM allows convenient access but consumes significant memory']}, {'end': 1729.43, 'segs': [{'end': 1432.227, 'src': 'heatmap', 'start': 1383.313, 'weight': 2, 'content': [{'end': 1389.855, 'text': "split with no arguments, then it splits on white space and that's going to turn out to be a pretty reasonable behavior for this program.", 'start': 1383.313, 'duration': 6.542}, {'end': 1395.898, 'text': "So for word count, I'm just looking for split with no arguments, so you just get the words and it's just automatic.", 'start': 1389.895, 'duration': 6.003}, {'end': 1398.979, 'text': "It knows what a tab is, what a new line is, it'll do something kind of reasonable.", 'start': 1396.058, 'duration': 2.921}, {'end': 1401.96, 'text': "Tomorrow, with regular expressions, we'll do a better job.", 'start': 1400.259, 'duration': 1.701}, {'end': 1403.321, 'text': 'But for today, this is sufficient.', 'start': 1401.98, 'duration': 1.341}, {'end': 1405.622, 'text': 'All right.', 'start': 1405.262, 'duration': 0.36}, {'end': 1410.284, 'text': 'So what I want you to do is process the whole file and, like, figure out what the words are.', 'start': 1406.182, 'duration': 4.102}, {'end': 1414.006, 'text': 'And then you can debug on small.text.', 'start': 1411.305, 'duration': 2.701}, {'end': 1416.367, 'text': "And then it's a little more fun.", 'start': 1415.246, 'duration': 1.121}, {'end': 1419.328, 'text': 'Then we also just have the entire text of Alice in Wonderland.', 'start': 1416.727, 'duration': 2.601}, {'end': 1422.37, 'text': 'And so you can just process that as well.', 'start': 1420.329, 'duration': 2.041}, {'end': 1432.227, 'text': 'Something a little dopey is happening here where like the word while appears 20 times, but the word while followed by a comma appears four times.', 'start': 1424.14, 'duration': 8.087}], 'summary': 'Using split with no arguments for word count, and planning to use regular expressions for better job tomorrow.', 'duration': 39.057, 'max_score': 1383.313, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1383313.jpg'}, {'end': 1493.84, 'src': 'embed', 'start': 1461.853, 'weight': 0, 'content': [{'end': 1464.296, 'text': "But, you know, memory, algorithms, it's just not that quick.", 'start': 1461.853, 'duration': 2.443}, {'end': 1466.558, 'text': "That's just, you know, you should know.", 'start': 1465.477, 'duration': 1.081}, {'end': 1473.504, 'text': "That's one of the things that, And yet I just processed the entire Alice in Wonderland And like whatever, if you time this,", 'start': 1466.798, 'duration': 6.706}, {'end': 1474.625, 'text': "it's like about 20th of a second.", 'start': 1473.504, 'duration': 1.121}, {'end': 1481.01, 'text': 'And this code is just written in the most obvious, convenient way, the laziest way I can think of, which is of course the way all my code looks.', 'start': 1474.745, 'duration': 6.265}, {'end': 1485.794, 'text': 'So, on the one hand, you know, Python is not the quickest language.', 'start': 1482.451, 'duration': 3.343}, {'end': 1488.616, 'text': 'On the other hand, most things are just kind of IO bound,', 'start': 1485.874, 'duration': 2.742}, {'end': 1493.84, 'text': 'like probably saving that last nanosecond of CPU time is maybe not the best use of your time where you want stuff to work.', 'start': 1488.616, 'duration': 5.224}], 'summary': 'Processing entire alice in wonderland in python takes about 20th of a second.', 'duration': 31.987, 'max_score': 1461.853, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1461853.jpg'}, {'end': 1545.44, 'src': 'embed', 'start': 1513.854, 'weight': 3, 'content': [{'end': 1516.056, 'text': 'So then I want to have top count.', 'start': 1513.854, 'duration': 2.202}, {'end': 1519.598, 'text': "Oops, let's do top count on Alice in Wonderland.", 'start': 1517.237, 'duration': 2.361}, {'end': 1522.821, 'text': 'Do you guys have a 20th of a second to spare? Sure, all right.', 'start': 1520.579, 'duration': 2.242}, {'end': 1532.094, 'text': "All right, so what does that do? Yeah, it's by the frequency.", 'start': 1524.442, 'duration': 7.652}, {'end': 1534.275, 'text': 'Yeah, so what appeared most often.', 'start': 1532.814, 'duration': 1.461}, {'end': 1545.44, 'text': 'Now, just in terms of writing code, well, these both use a dictionary which has the word as the key and the count as the value.', 'start': 1534.835, 'duration': 10.605}], 'summary': 'Analyzing the frequency of words using a dictionary to find top count.', 'duration': 31.586, 'max_score': 1513.854, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1513854.jpg'}, {'end': 1656.534, 'src': 'embed', 'start': 1626.902, 'weight': 1, 'content': [{'end': 1628.163, 'text': "Sorry, so I'll tell you what this program does.", 'start': 1626.902, 'duration': 1.261}, {'end': 1629.963, 'text': "It's a fun program.", 'start': 1629.103, 'duration': 0.86}, {'end': 1635.586, 'text': "It uses, actually, in terms of coding technique, it's very similar to word count, same level of abstraction.", 'start': 1630.003, 'duration': 5.583}, {'end': 1636.606, 'text': 'It just does something different.', 'start': 1635.806, 'duration': 0.8}, {'end': 1644.789, 'text': 'What this program does, and also it shows how Python is actually quite fast in some sense, it looks at every word that appears in the text.', 'start': 1637.026, 'duration': 7.763}, {'end': 1652.873, 'text': 'And for every word, it just keeps a Python list of all the words that ever appear after it in the entire text.', 'start': 1645.31, 'duration': 7.563}, {'end': 1656.534, 'text': 'You can sort of imagine building a Python dictionary that just sort of tracks this.', 'start': 1653.573, 'duration': 2.961}], 'summary': 'Python program analyzes text to create dictionary of words and their subsequent appearances.', 'duration': 29.632, 'max_score': 1626.902, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1626902.jpg'}], 'start': 1286.802, 'title': 'Word count exercise and python efficiency', 'summary': "Introduces the word count exercise using python's .split function to count word occurrences, and explores python's efficiency, processing 'alice in wonderland' in about 20th of a second, and its use of dictionaries for word count and mimic programs.", 'chapters': [{'end': 1442.917, 'start': 1286.802, 'title': 'Word count exercise', 'summary': "Introduces the word count exercise, which involves creating a program to count the occurrences of words in a file, and emphasizes the use of python's .split function and the conversion to lowercase.", 'duration': 156.115, 'highlights': ["The Word Count exercise involves creating a program to count the occurrences of words in a file, using Python's .split function to separate words and converting them to lowercase for accurate counting.", 'The program uses the .split function with no arguments to split the words based on whitespace, providing a reasonable behavior for the Word Count exercise.', "The chapter emphasizes the need to process the entire file and debug using small.text before moving on to processing larger texts like 'Alice in Wonderland'.", "The limitations of the current strategy, such as counting 'while' and 'while,' separately, are acknowledged, with a promise to address punctuation handling in the upcoming session."]}, {'end': 1729.43, 'start': 1442.937, 'title': 'Python: efficiency and program functionality', 'summary': "Explores the efficiency and functionality of python, highlighting its speed in processing the entire 'alice in wonderland' in about 20th of a second, and the utilization of dictionaries for word count and mimic programs.", 'duration': 286.493, 'highlights': ["Python can process the entire 'Alice in Wonderland' in about 20th of a second, showcasing its efficiency.", 'The word count and top count programs both utilize a dictionary with words as keys and counts as values, emphasizing the importance of reusing code.', 'The Mimic program uses a Python list to track words that appear after each word in the text, showcasing a different functionality of Python.']}], 'duration': 442.628, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/haycL41dAhg/pics/haycL41dAhg1286802.jpg', 'highlights': ["Python can process 'Alice in Wonderland' in about 20th of a second, showcasing its efficiency.", "The Word Count exercise involves creating a program to count the occurrences of words in a file, using Python's .split function to separate words and converting them to lowercase for accurate counting.", 'The program uses the .split function with no arguments to split the words based on whitespace, providing a reasonable behavior for the Word Count exercise.', 'The word count and top count programs both utilize a dictionary with words as keys and counts as values, emphasizing the importance of reusing code.', "The chapter emphasizes the need to process the entire file and debug using small.text before moving on to processing larger texts like 'Alice in Wonderland'."]}], 'highlights': ['Python dictionaries provide constant time lookup for key retrieval', 'Dictionaries efficiently organize incoherent data, as demonstrated by counting IP addresses in Apache log files', "Python can process 'Alice in Wonderland' in about 20th of a second, showcasing its efficiency", 'The Word Count exercise involves creating a program to count the occurrences of words in a file', 'The last exercise integrates file reading, lists, and strings', 'The analogy of Google running as a large hash table emphasizes the powerful and efficient nature of dictionaries', 'The importance of incremental programming in Python, suggesting to print the current state of the program to iterate tightly and efficiently', 'Using clear and descriptive variable names in Python is crucial, as it helps in keeping track of variable types and reduces the chances of errors', 'Reading entire file into one string is phenomenally convenient for some operations', 'The program uses the .split function with no arguments to split the words based on whitespace, providing a reasonable behavior for the Word Count exercise', 'The .items method retrieves key-value pairs as tuples for looping operations', 'The .values method pulls out a linear list of values from the dictionary', 'The .keys method returns a list of keys from the dictionary', "The dot get method returns 'none' if the value is not present in the dictionary", "The 'in' method is used to test if a value is present in the dictionary", 'Attempting to retrieve a non-existent key in the dictionary results in a key error', 'The significance of conscious and descriptive variable naming in Python is highlighted, particularly in debugging basic Python programs', 'The efficiency of processing large files without consuming excessive RAM', 'Importance of closing the file handle at the end', 'Syntax for inhibiting the last new line in Python', "When working with a list of items in Python, it is recommended to use a variable name ending in 'S' to indicate that it is a list of things"]}