WEBVTT 00:00:00.001 --> 00:00:06.080 Hello and welcome to Python Bytes, where we deliver Python news and headlines directly to your earbuds. 00:00:06.080 --> 00:00:12.320 It's Tuesday, May 30th, 2017, and this is episode 28 of Python Bytes. 00:00:12.320 --> 00:00:13.680 And I'm Michael Kennedy. 00:00:13.680 --> 00:00:14.760 And I'm Brian Okken. 00:00:14.760 --> 00:00:17.180 Brian, can you believe that we've done 28 episodes already? 00:00:17.180 --> 00:00:20.820 No, I can't. I was telling somebody about the show recently and I said, 00:00:20.820 --> 00:00:24.260 oh, we've only done like, oh my gosh, we've done like 27 episodes already. 00:00:24.260 --> 00:00:27.480 Yeah, we've done over half a year in the history of Python Podcast. 00:00:27.700 --> 00:00:34.000 I think over half a year's worth, over 20 episodes, makes it like one of the longest running podcasts of all time, actually. 00:00:34.000 --> 00:00:38.620 Right? A lot of the other ones, they sort of cut out early 20s, you know, things like that. 00:00:38.620 --> 00:00:39.180 Oh yeah, that's true. 00:00:39.180 --> 00:00:42.920 Yeah, I mean, Talk Python and Podcasting, they've been going for a while, but still. 00:00:42.920 --> 00:00:50.600 One of the primary rules that, or documents, or enhancements, that tells us how we should write our code is PEP 8, right? 00:00:50.600 --> 00:00:55.940 Yeah, definitely everybody that's really into Python knows about PEP 8. 00:00:56.300 --> 00:01:04.680 But sometimes when you mention, hey, you should follow PEP 8 to somebody new, it's not really that easy to get them up to speed. 00:01:04.680 --> 00:01:06.280 You know, it's not that hard to read. 00:01:06.280 --> 00:01:10.360 But I didn't know about this thing called PEP 8.org. 00:01:10.360 --> 00:01:13.000 And so I just stumbled across this recently. 00:01:13.260 --> 00:01:15.180 And it's from Kenneth Reitz. 00:01:15.180 --> 00:01:21.380 And it's just an easy to use, it is the, just PEP 8, the style guide. 00:01:21.380 --> 00:01:25.380 It's a nice webpage with, styled nicely. 00:01:25.740 --> 00:01:29.160 It's got red for bad examples and green for good examples. 00:01:29.160 --> 00:01:32.240 And it's got a nice index on the left that you can click through. 00:01:32.240 --> 00:01:35.220 Yeah, it's definitely, yeah, it's a really nice and navigable thing. 00:01:35.220 --> 00:01:39.140 And you're right, like, the green do this, red don't do that. 00:01:39.140 --> 00:01:47.120 And, you know, even little touches like the code samples that demonstrate good and bad, just basically any of the code samples that demonstrate anything. 00:01:47.120 --> 00:01:51.460 Are color-coded, which is, like, surprisingly delightful. 00:01:51.460 --> 00:01:51.800 Yeah. 00:01:51.800 --> 00:01:57.460 And I also like, because there's the index there, they're all anchors in the webpage. 00:01:57.460 --> 00:01:59.480 So you can take one of those. 00:01:59.480 --> 00:02:08.720 And if you want to mention a particular guideline to somebody, maybe a coworker that's not following it, you can email them that link and say, hey, could you read this? 00:02:08.720 --> 00:02:09.220 Exactly. 00:02:09.220 --> 00:02:12.020 Yeah, put that in your get issue response. 00:02:12.020 --> 00:02:15.740 Like, I'm willing to take your PR, but hold on, you got to fix this first. 00:02:15.740 --> 00:02:16.380 Yeah. 00:02:16.680 --> 00:02:22.640 And, but one of the things that I always want to mention when I talk about Pep 8 is don't be a Pep 8 bully. 00:02:22.640 --> 00:02:27.860 The first line of Pep 8 talks about hobgoblins or something like that. 00:02:27.860 --> 00:02:29.680 And basically... 00:02:29.680 --> 00:02:30.040 Yes. 00:02:30.040 --> 00:02:34.940 Blondly following rules is the hobgoblins of little minds or something to this effect, yeah? 00:02:34.940 --> 00:02:35.760 Yeah. 00:02:35.760 --> 00:02:40.820 So somebody might have a decent reason for not following Pep 8. 00:02:40.820 --> 00:02:44.400 So tread carefully when you try to get somebody to follow it. 00:02:44.780 --> 00:02:57.680 If you haven't stumbled across Pep 8 before, which is kind of hard to think that's possible if you're listening to this podcast, it does describe itself as being the style guide for the standard library for Python. 00:02:57.680 --> 00:03:01.160 But it's a lot more than that. 00:03:01.160 --> 00:03:05.400 Most open source Python projects follow it to some degree, don't you think? 00:03:05.400 --> 00:03:06.020 Right, yeah. 00:03:06.020 --> 00:03:09.660 And you can set up linters that will, like, mention violations. 00:03:09.660 --> 00:03:27.300 So, for example, I think cookie cutter, if you do a PR back to them and you do something like, say, write an 81 character line, it will fail the automated build and say we're not going to accept it because it fails Flake 8 or something to this effect. 00:03:27.300 --> 00:03:27.480 Right. 00:03:27.480 --> 00:03:28.160 Okay. 00:03:28.160 --> 00:03:28.460 Yeah. 00:03:28.460 --> 00:03:35.900 You know, I suspect everyone, pretty much everyone's heard of Pep 8, but I'm not sure everyone has actually taken the time to read through Pep 8. 00:03:35.900 --> 00:03:37.520 And I think that this thing is more readable. 00:03:37.520 --> 00:03:41.140 So it's probably, you know, if you're in that group, then go check it out, pepe.org. 00:03:41.140 --> 00:03:41.340 Okay. 00:03:41.340 --> 00:03:43.040 So what's next? 00:03:43.040 --> 00:03:45.200 I want to talk about asynchronous stuff. 00:03:45.200 --> 00:03:45.960 Is it surprising? 00:03:45.960 --> 00:03:47.340 I always talk about asynchronous stuff. 00:03:48.840 --> 00:03:54.100 So there's this new project called Tokio, I think is how you might say it, T-O-K-I-O. 00:03:54.100 --> 00:04:02.200 And at the heart of AsyncIO and the Async and Await stuff are these things called Async Event Loops and whatnot. 00:04:02.200 --> 00:04:05.180 And this is one of those. 00:04:05.180 --> 00:04:09.620 We'd previously spoken about Sanic and some of these faster web frameworks. 00:04:09.620 --> 00:04:13.340 And their magic was that they run on top of this thing called uv Loop. 00:04:13.920 --> 00:04:20.740 And uv Loop is, I think, implemented in C and is an alternate implementation of this internal AsyncIO loop. 00:04:20.740 --> 00:04:25.860 Well, Tokoy is a similar concept, but implemented in Rust. 00:04:25.860 --> 00:04:32.700 So Rust is a compiled low-level language such as, you know, like C. 00:04:32.700 --> 00:04:34.200 I mean, you can debate with this low-level. 00:04:34.200 --> 00:04:35.120 I feel like it is. 00:04:35.120 --> 00:04:36.640 It's closer to the metal anyway. 00:04:36.640 --> 00:04:38.240 It's a compiled language. 00:04:38.960 --> 00:04:44.780 And it's supposed to be a little better for threading, a little better for memory management and safety. 00:04:44.780 --> 00:04:49.140 So it's a little bit of a safer, more modern, low-level way to implement this. 00:04:49.140 --> 00:04:57.080 And I just thought it was kind of an interesting example that you could go check out and say, like, here's integration of Python with Rust. 00:04:57.080 --> 00:04:57.800 Okay. 00:04:57.800 --> 00:05:00.280 So it's a Python thing? 00:05:00.280 --> 00:05:00.680 Yeah. 00:05:00.680 --> 00:05:01.600 So you use it from Python. 00:05:01.600 --> 00:05:04.620 But instead of having, like, a C extension, you have a Rust extension. 00:05:04.620 --> 00:05:05.100 Oh, okay. 00:05:05.100 --> 00:05:05.640 That makes sense. 00:05:05.640 --> 00:05:06.620 Took me a while to catch up. 00:05:06.720 --> 00:05:07.120 Yeah, yeah, yeah. 00:05:07.120 --> 00:05:14.240 So, like, the heart of the asyncIO event loop is, like, written in C when you're looking at a uvloop. 00:05:14.240 --> 00:05:15.380 Here it's written in Rust. 00:05:15.380 --> 00:05:18.180 And so here's, like, an interesting internal bit. 00:05:18.180 --> 00:05:24.480 But you basically plug it into your Python code, and then you can, you know, work with the async event loop like you normally would. 00:05:24.480 --> 00:05:24.740 Okay. 00:05:24.740 --> 00:05:29.040 And I'm guessing it might be pronounced Tokyo, but just guessing. 00:05:29.040 --> 00:05:29.440 Tokyo? 00:05:29.440 --> 00:05:29.480 Tokyo? 00:05:29.480 --> 00:05:29.880 Yeah, yeah. 00:05:29.880 --> 00:05:30.100 Okay. 00:05:30.100 --> 00:05:30.520 Tokyo. 00:05:30.520 --> 00:05:31.180 You're probably right. 00:05:31.180 --> 00:05:34.320 You're probably right about that. 00:05:34.320 --> 00:05:36.660 So, yeah, cool. 00:05:37.320 --> 00:05:40.120 And the project's still super early stage development. 00:05:40.120 --> 00:05:46.960 So if you're into Rust or you want to play with Rust and you would like it, a lot of people ask me, like, hey, I want to do something open source. 00:05:46.960 --> 00:05:48.640 Is there an approachable small project? 00:05:48.640 --> 00:05:50.200 This thing's pretty early days. 00:05:50.200 --> 00:05:55.440 And so it's probably not too complicated to jump in and play around with if people are looking for some project to get involved with. 00:05:55.440 --> 00:05:56.140 Well, that's great. 00:05:56.140 --> 00:05:57.180 Yeah, absolutely. 00:05:57.180 --> 00:05:59.360 Tell me about some boilerplate. 00:05:59.360 --> 00:06:02.860 Well, this is – I've got another project that is fairly early. 00:06:02.860 --> 00:06:05.680 I guess I was just assuming it's fairly early in the project. 00:06:05.680 --> 00:06:08.100 But I stumbled across – stumbled. 00:06:08.100 --> 00:06:09.380 I'm saying that a lot today. 00:06:09.380 --> 00:06:13.240 I came across this – a website called Python Boilerplate. 00:06:13.400 --> 00:06:16.120 It's python-boilerplate.com. 00:06:16.120 --> 00:06:21.380 And it's addictively fun, at least right at first. 00:06:21.380 --> 00:06:23.260 I wouldn't try it on a phone. 00:06:23.260 --> 00:06:25.200 Actually, I haven't tried it on a phone. 00:06:25.200 --> 00:06:29.100 But it's got a whole bunch of push buttons and stuff. 00:06:29.100 --> 00:06:32.780 And you can say which sort of boilerplate you want to have it spit out. 00:06:33.200 --> 00:06:36.880 And you can select Python 2 even or Python 3. 00:06:36.880 --> 00:06:39.780 Luckily, it does default to Python 3. 00:06:39.780 --> 00:06:49.300 And you can say whether or not you want an executable – whether it's an executable script or – and whether or not you want arg parse stuff in there. 00:06:49.300 --> 00:06:55.620 Which actually, somebody that wants to add arg parse stuff, it's kind of nice to have some built-in boilerplate of examples. 00:06:55.620 --> 00:06:56.140 Yeah. 00:06:56.300 --> 00:07:04.660 So it's a little bit like what Cookie Cutter does for large projects where you can say, I want to generate kind of a starter code, a starter skeleton. 00:07:04.660 --> 00:07:10.160 But it's more like that but for command line apps, CLI apps, right? 00:07:10.160 --> 00:07:10.580 Yeah. 00:07:10.580 --> 00:07:11.780 Smaller little projects. 00:07:11.780 --> 00:07:22.100 And it even, like, puts together a preliminary – like, for instance, if you add Flask or pytest, for instance, it'll add your requirements.txt to it. 00:07:22.660 --> 00:07:28.120 So it's a similar vein as Cookie Cutter but a little more interactive and it's fun. 00:07:28.120 --> 00:07:28.860 Yeah, I know. 00:07:28.860 --> 00:07:29.200 I like it. 00:07:29.200 --> 00:07:30.080 People should check that out. 00:07:30.080 --> 00:07:31.920 So that one's fun. 00:07:31.920 --> 00:07:33.800 We recently went to PyCon. 00:07:33.800 --> 00:07:34.440 It was awesome, right? 00:07:34.440 --> 00:07:35.500 It was very awesome, yeah. 00:07:35.500 --> 00:07:40.060 Hopefully this year people will take us seriously when we say, get your tickets before it sells out. 00:07:40.060 --> 00:07:50.140 Because – anyway, one of the things that's really cool that I really liked from PyCon was the presentation that Instagram – the folks from Instagram did. 00:07:51.180 --> 00:07:54.520 And luckily this is all on YouTube so people can check it out. 00:07:54.520 --> 00:08:06.660 So Instagram, they're probably not the biggest but they're one of the biggest by traffic number of users and whatnot, consumers or users of Python for their web apps and their backend services. 00:08:06.660 --> 00:08:09.040 Like, they seriously use Python. 00:08:09.040 --> 00:08:10.880 They use Django in many, many places. 00:08:12.000 --> 00:08:20.100 And they had found themselves in a bit of a situation like many, many of our listeners probably find themselves. 00:08:20.100 --> 00:08:23.860 But to a degree that is way, way higher, right? 00:08:23.860 --> 00:08:26.880 So they've got hundreds of millions of users. 00:08:26.880 --> 00:08:30.060 Many, many, who knows how many thousand lines of Python. 00:08:30.340 --> 00:08:38.860 And they were stuck on Python 2.7 and Django, I think they said 1.3, which is years out of date. 00:08:38.860 --> 00:08:40.560 It's quite out of date. 00:08:40.560 --> 00:08:42.080 Like, the current one is 1.8. 00:08:42.080 --> 00:08:44.060 The one people are working on is 2. 00:08:44.060 --> 00:08:49.480 The big news about Django 2 is it's only going to support Python 3, right? 00:08:49.500 --> 00:08:50.760 That was the big news there. 00:08:50.760 --> 00:08:57.740 And so they said, we somehow need to get onto Python 3, right? 00:08:57.740 --> 00:09:00.180 A lot of companies say we have this huge bit of code. 00:09:00.180 --> 00:09:02.960 And so, well, I'll throw my hands up in the air. 00:09:02.960 --> 00:09:04.760 We just couldn't possibly switch, right? 00:09:04.760 --> 00:09:05.560 It's just too much work. 00:09:05.560 --> 00:09:06.380 It's too much risk. 00:09:06.380 --> 00:09:12.980 If you watch this presentation, there's almost no way you can look at this and go, 00:09:12.980 --> 00:09:16.320 oh, there's no way we can switch to Python 3 after you see what they went through. 00:09:16.320 --> 00:09:18.040 So it's really intense. 00:09:18.040 --> 00:09:22.700 So, for example, they don't believe in branches in their Git repo. 00:09:22.700 --> 00:09:23.860 Wow, I must have missed that. 00:09:23.860 --> 00:09:24.480 That's interesting. 00:09:24.480 --> 00:09:24.880 Yeah. 00:09:24.880 --> 00:09:25.960 It's interesting, right? 00:09:25.960 --> 00:09:33.320 Because I think to some degree rightly feel that the farther you are away from master or, yeah, from master, 00:09:33.320 --> 00:09:38.360 what they're calling it, the more it's going to be hard to integrate that back in. 00:09:38.360 --> 00:09:40.480 And the more you could introduce trouble by merging that back in. 00:09:40.480 --> 00:09:43.300 So what they do is they use feature switches. 00:09:43.300 --> 00:09:47.240 So if you're working on a new feature, there's a config on your dev server that says, 00:09:47.460 --> 00:09:48.200 enable this feature. 00:09:48.200 --> 00:09:50.960 But in production, it might be turned off. 00:09:50.960 --> 00:09:52.020 So they're shipping. 00:09:52.020 --> 00:09:59.520 They said they check in to the master branch quite often, like many times a day. 00:09:59.520 --> 00:10:03.740 And with an hour of that check-in, it's pushed to production, even when the features are not done. 00:10:03.740 --> 00:10:04.160 Right? 00:10:04.560 --> 00:10:14.280 So now they have this huge, huge branch of Python code where lots of the libraries and modules and stuff are shared across different services and different servers. 00:10:14.680 --> 00:10:17.180 It runs on our old version of Django on Python 2.7. 00:10:17.180 --> 00:10:20.820 And they're like, all right, what we're going to do is we're going to upgrade to Python 3. 00:10:20.820 --> 00:10:22.200 And we're not going to branch. 00:10:22.200 --> 00:10:26.580 We're going to keep shipping on this main branch and convert it to Python 3. 00:10:26.880 --> 00:10:29.020 We're going to upgrade like years worth of Django. 00:10:29.020 --> 00:10:33.600 I'm going to keep shipping on Python to production and so on. 00:10:33.600 --> 00:10:44.280 And so the process that they went through and the little steps that they took, and even for you, the testing procedures they went through to make this work was really, really interesting. 00:10:44.280 --> 00:10:47.480 So basically, I'll give you guys the summary. 00:10:47.480 --> 00:10:49.760 If you want to watch the video, it's highly recommended. 00:10:49.760 --> 00:10:57.280 But it's really a concrete roadmap for every large project, every large company with lots of users and traffic to switch. 00:10:57.280 --> 00:11:08.900 So they said they got between 12% and 40% performance improvement, depending on where you look, like, say, the web tier versus the async queue tier and so on. 00:11:08.900 --> 00:11:12.020 And I think like 30% better memory usage. 00:11:12.020 --> 00:11:14.760 So just like straight across the board, everything was better. 00:11:14.760 --> 00:11:18.000 And they haven't even started using the asyncio stuff. 00:11:18.000 --> 00:11:22.060 And they're super happy now that they can switch to a new version of Django. 00:11:22.060 --> 00:11:26.480 Something cool comes out in terms of performance, say, like Python 3.7. 00:11:26.480 --> 00:11:28.500 Some function call becomes much faster. 00:11:28.500 --> 00:11:29.460 They just get that. 00:11:29.460 --> 00:11:31.680 They don't have to, like, go, well, that'd be nice, right? 00:11:31.680 --> 00:11:36.680 They basically, so they get to be part of the forefront of Python once again, and they're happy about it. 00:11:36.680 --> 00:11:41.680 So then they, like, start converting their code base so that it could run on Python 3. 00:11:41.840 --> 00:11:44.980 But they were still deploying on Python 2.7. 00:11:44.980 --> 00:11:45.340 Yes. 00:11:45.340 --> 00:11:46.780 Yes, exactly. 00:11:46.780 --> 00:11:56.740 And then eventually one of the changes, one of the steps they made was we're going to make all the developers run and develop on Python 3, but still deploy to Python 2. 00:11:57.020 --> 00:12:04.600 And so that was one of the main, like, checks and balances was the developers will start hitting these bugs locally. 00:12:04.600 --> 00:12:06.140 I will never push it out. 00:12:06.140 --> 00:12:08.500 And then they didn't push it out to production fully then. 00:12:08.500 --> 00:12:10.820 They pushed it out to just Facebook employees. 00:12:11.220 --> 00:12:14.300 And then they pushed it out to 0.1% of their users. 00:12:14.300 --> 00:12:14.760 Yeah. 00:12:14.760 --> 00:12:15.680 To see how that worked. 00:12:15.680 --> 00:12:19.700 And then finally they started, they switched to, like, 20% and then, like, they pushed it all the way out. 00:12:19.700 --> 00:12:20.220 Something like that. 00:12:20.220 --> 00:12:20.400 Yeah. 00:12:20.400 --> 00:12:20.920 Yeah. 00:12:20.920 --> 00:12:22.360 So it was a really interesting rollout. 00:12:22.360 --> 00:12:27.320 And on their testing, they had, like, at first there was a bunch of tests that just couldn't be fixed. 00:12:27.860 --> 00:12:32.280 And so they set up a, like, these are the tests that are included in the automated build. 00:12:32.280 --> 00:12:38.580 And slowly as they migrated tests, they added them to also include this so they would not regress back to be broken. 00:12:38.580 --> 00:12:38.860 Yeah. 00:12:38.860 --> 00:12:41.600 And they kind of chopped their way through that. 00:12:41.600 --> 00:12:45.200 And then eventually they said, okay, the default is new tests all have to pass on Python 3. 00:12:45.200 --> 00:12:49.080 And the old ones are going to go into this exclude list until we get the failing ones to 0. 00:12:49.080 --> 00:12:51.060 And I really liked the presentation. 00:12:51.060 --> 00:12:54.560 And I liked how they talked about actually a lot of the points that they went through. 00:12:54.740 --> 00:12:59.140 And it's a lot, I think the example is a good example for any project. 00:12:59.140 --> 00:13:04.960 But the, I also, I really liked the, just the reality that it's not trivial. 00:13:04.960 --> 00:13:05.340 Yeah. 00:13:05.340 --> 00:13:06.420 No, it wasn't trivial. 00:13:06.420 --> 00:13:09.100 It was like six months or four months or something huge. 00:13:09.100 --> 00:13:09.260 Yeah. 00:13:09.260 --> 00:13:11.420 But very doable and while in production. 00:13:11.420 --> 00:13:12.060 That's pretty cool. 00:13:12.060 --> 00:13:12.340 Yeah. 00:13:12.340 --> 00:13:14.040 And they also kept shipping new features, right? 00:13:14.040 --> 00:13:15.120 That was one of their requirements. 00:13:15.120 --> 00:13:15.460 Right. 00:13:15.460 --> 00:13:17.600 So they shipped a bunch of new features at the same time. 00:13:17.600 --> 00:13:20.920 I bet they used at least one underscore in their code when they did that. 00:13:20.920 --> 00:13:22.200 Probably several underscores. 00:13:22.200 --> 00:13:22.440 Yeah. 00:13:22.900 --> 00:13:27.900 We've featured Dan Bader on the show a lot, but this is a pretty cool article. 00:13:27.900 --> 00:13:30.120 The meaning of underscores in Python. 00:13:30.120 --> 00:13:31.580 And again, 00:13:31.580 --> 00:13:34.600 I think this falls into the realm of like what you said with PEP 8, right? 00:13:34.600 --> 00:13:39.100 Like a lot of people are seeing these, but maybe they haven't really looked specifically at what it's about, right? 00:13:39.100 --> 00:13:39.560 Yeah. 00:13:39.660 --> 00:13:42.960 And also he goes through pretty much all the different meanings. 00:13:42.960 --> 00:13:51.520 But one of the things that I, it took me a while to understand is that when people say dunder, they mean something with two underscores on both ends. 00:13:51.520 --> 00:13:51.900 Yes. 00:13:51.900 --> 00:13:53.560 Shortened of double underscore. 00:13:53.560 --> 00:13:55.740 So it's a good list. 00:13:55.740 --> 00:14:04.360 He talks about the leading underscore, meaning that it's sort of by convention, private for, or internal use only. 00:14:04.360 --> 00:14:10.120 But, and I added a note in our show notes that that doesn't apply to named tuple. 00:14:10.120 --> 00:14:15.300 Named tuple has its functions starting with leading underscore, but you can still use them. 00:14:15.300 --> 00:14:16.100 That's what they're for. 00:14:16.240 --> 00:14:16.360 Yeah. 00:14:16.360 --> 00:14:16.700 Nice. 00:14:16.700 --> 00:14:17.140 Nice. 00:14:17.140 --> 00:14:17.840 Yeah. 00:14:17.840 --> 00:14:22.220 I was just pairing with somebody today and said, what does class underscore mean? 00:14:22.220 --> 00:14:23.840 Like why is the underscore there? 00:14:23.840 --> 00:14:24.400 Oh yeah. 00:14:24.400 --> 00:14:24.900 Right. 00:14:24.900 --> 00:14:34.120 So if that's the trailing underscore, it's because somebody doesn't want to collide with a Python keyword or something. 00:14:34.120 --> 00:14:35.100 Yeah, exactly. 00:14:35.100 --> 00:14:36.040 Like it's class. 00:14:36.040 --> 00:14:36.860 So class underscore. 00:14:36.860 --> 00:14:37.080 Yeah. 00:14:37.080 --> 00:14:44.760 And I do like, I actually like that convention a lot better than having like my class or this class or something like that. 00:14:44.760 --> 00:14:45.740 I know that really. 00:14:45.940 --> 00:14:46.080 Yeah. 00:14:46.080 --> 00:14:52.200 And one of the things that a lot of people don't, that I was surprised by when I first learned about it is a single underscore by itself. 00:14:52.200 --> 00:14:52.560 Yes. 00:14:52.560 --> 00:14:53.580 That's my, one of my favorites. 00:14:53.580 --> 00:15:02.060 And that's a, that's a, I don't care variable that you can, like, if you have to assign a variable, something to a variable, but you're not going to use it anymore or use it at all. 00:15:02.060 --> 00:15:03.680 That's a decent one. 00:15:03.680 --> 00:15:05.880 And the warning, you don't get a warning for that. 00:15:05.880 --> 00:15:08.780 If it's a, something assigned and never used. 00:15:08.780 --> 00:15:09.260 Exactly. 00:15:09.260 --> 00:15:10.360 It's meant to not be used. 00:15:10.360 --> 00:15:10.600 Yeah. 00:15:10.600 --> 00:15:10.780 Yeah. 00:15:10.780 --> 00:15:15.640 I mean, the couple of places I see that like a tuple unpacking, when you don't care about all the 00:15:15.640 --> 00:15:17.320 values is kind of good. 00:15:17.320 --> 00:15:22.560 If you say, I just want to do a loop from one to 10, but I don't care about the number. 00:15:22.560 --> 00:15:23.640 I just want to do it 10 times. 00:15:23.640 --> 00:15:28.500 You could say four underscore in range, you know, zero, 10, whatever, things like that. 00:15:28.500 --> 00:15:29.660 That's a good use for that. 00:15:29.660 --> 00:15:29.920 Yeah. 00:15:29.920 --> 00:15:30.140 Yeah. 00:15:30.280 --> 00:15:33.200 The other place that I really liked this is where I have function signatures. 00:15:33.200 --> 00:15:35.940 I have to match, but I don't care about the variables. 00:15:35.940 --> 00:15:40.800 So for example, in the web methods, a lot of them take request as a parameter. 00:15:40.800 --> 00:15:47.260 And if you don't put the request parameter there, like the framework will fail to like try to pass it and won't like match and it'll crash and all that. 00:15:47.340 --> 00:15:50.800 But I don't care about calling the request variable or working with it. 00:15:50.800 --> 00:15:53.280 So you'll get like a flake eight violation. 00:15:53.280 --> 00:15:54.200 You're not using it. 00:15:54.200 --> 00:15:55.100 So underscore. 00:15:55.420 --> 00:15:57.980 In that case, can you use it multiple times? 00:15:57.980 --> 00:16:00.980 Like, can you have multiple parameter names that are underscore? 00:16:00.980 --> 00:16:01.660 I think so. 00:16:01.660 --> 00:16:01.820 Yeah. 00:16:01.820 --> 00:16:07.440 I mean, you just like blast away the previous value stored in underscore, but if you're really using it as like, I don't care, then it's fine. 00:16:07.440 --> 00:16:07.700 Cool. 00:16:07.700 --> 00:16:08.220 Okay. 00:16:08.220 --> 00:16:09.560 Yeah, absolutely. 00:16:09.560 --> 00:16:11.740 So the underscore is definitely good. 00:16:11.740 --> 00:16:13.960 If you're not familiar with that, check out Dan's article. 00:16:13.960 --> 00:16:14.820 It's a good one. 00:16:14.820 --> 00:16:18.740 So let's close this out with a little bit of a look towards the future. 00:16:18.740 --> 00:16:19.500 Okay. 00:16:19.500 --> 00:16:24.260 And we talked about recently the Stack Overflow tools, trends tool. 00:16:24.780 --> 00:16:33.080 And when Stack Overflow released it, one of the things that they featured right up in the front was like language popularity for a few languages, including Python. 00:16:33.080 --> 00:16:34.040 And it looked pretty good, right? 00:16:34.040 --> 00:16:34.420 Yeah. 00:16:34.420 --> 00:16:34.700 Yeah. 00:16:34.700 --> 00:16:35.480 So I want to come back. 00:16:35.480 --> 00:16:44.760 There's a guy who wrote a Medium post that actually dug into this quite a bit and played around with it and said, the future is looking bright for Python. 00:16:44.760 --> 00:16:50.060 And basically took that tool and did a little better analysis with it than we did. 00:16:50.060 --> 00:16:58.920 And there's one chart that they put up as a standard chart at Stack Overflow since we covered it called the most popular languages trend chart. 00:16:59.320 --> 00:17:01.820 And that's got like 15 languages or something still. 00:17:01.820 --> 00:17:03.040 It's really completely overwhelming. 00:17:03.040 --> 00:17:07.420 But if you hover over the language names, it highlights them and dims the other so you can actually see it. 00:17:07.420 --> 00:17:07.720 Okay. 00:17:07.720 --> 00:17:08.280 Cool. 00:17:08.380 --> 00:17:18.080 What's really interesting is if you go through that chart and you hover over the languages, there are only like two languages that have upward trends and recently. 00:17:18.080 --> 00:17:22.180 And which one is the most steeply upward? 00:17:22.180 --> 00:17:24.440 Has the most positive derivative? 00:17:24.440 --> 00:17:25.180 Well, probably Python. 00:17:26.180 --> 00:17:27.140 Of course it does. 00:17:27.140 --> 00:17:29.520 Actually, by quite a large margin. 00:17:29.520 --> 00:17:34.400 And there's also a trend chart on there for Python 2 versus Python 3. 00:17:34.400 --> 00:17:37.540 And last year, Python 3 overtook Python 2. 00:17:37.540 --> 00:17:38.020 Oh, nice. 00:17:38.360 --> 00:17:43.400 So just a little, same kind of ideas with this trends, but just digging in a little more detail on it. 00:17:43.400 --> 00:17:44.180 It's kind of interesting. 00:17:44.180 --> 00:17:53.400 I thought it'd be fun to tie that together with the Instagram story so you can go back to your company, your boss, whatever, and go into life 2020 for Python 2. 00:17:53.400 --> 00:17:56.240 Django is no longer supporting Python 2. 00:17:56.240 --> 00:17:58.780 Look, the Python 3 is growing here. 00:17:58.780 --> 00:17:59.940 Just like all the good stuff, right? 00:17:59.940 --> 00:18:05.280 Bring it all together to help get a little more Python versus legacy Python in the world. 00:18:05.280 --> 00:18:13.260 Yeah, and I definitely don't hear, a couple years ago, we still heard people coming up with good reasons to stay on 2.7. 00:18:13.260 --> 00:18:15.920 And I don't hear anybody talking about that anymore. 00:18:15.920 --> 00:18:16.860 Nope. 00:18:16.860 --> 00:18:21.060 It's definitely, definitely, we've crossed over some sort of boundary, for sure. 00:18:21.060 --> 00:18:25.720 Well, hopefully also in the future, it'll bring us at least another half year of Python bytes. 00:18:25.720 --> 00:18:29.940 I'm pretty sure we can at least get another half year of this. 00:18:29.940 --> 00:18:30.320 Yeah, so. 00:18:30.320 --> 00:18:31.500 It's fun. 00:18:31.500 --> 00:18:33.120 That's all of our topics. 00:18:33.120 --> 00:18:34.920 Any news for us, Michael? 00:18:35.120 --> 00:18:36.000 No real news for me. 00:18:36.000 --> 00:18:40.000 I'm just recording podcasts like crazy, trying to get ahead for the summer. 00:18:40.000 --> 00:18:47.000 So I have, like I was just telling you, the opening of the show before we hit record, like eight episodes of Talk Python To Me. 00:18:47.000 --> 00:18:49.520 I'm recording over the next six, seven days. 00:18:49.520 --> 00:18:53.640 So there's going to be a whole bunch of good stuff lining up, and I'm excited about what's coming. 00:18:53.640 --> 00:18:54.180 How about you? 00:18:54.180 --> 00:18:56.360 I'm kicking off some more recording also. 00:18:57.140 --> 00:18:59.020 Definitely the book is still going strong. 00:18:59.020 --> 00:18:59.540 Yeah. 00:18:59.540 --> 00:19:03.060 And doing a lot of work on that. 00:19:03.060 --> 00:19:08.080 But I recorded an interview this morning, and I'll have at least a couple coming out in the next couple weeks. 00:19:08.080 --> 00:19:09.900 So Test and Code is not dead. 00:19:09.900 --> 00:19:11.240 It will come back. 00:19:11.240 --> 00:19:12.420 What was the topic? 00:19:12.420 --> 00:19:13.240 What did you record on today? 00:19:13.360 --> 00:19:17.420 Actually, I recorded somebody that does mobile testing. 00:19:17.420 --> 00:19:21.280 So mobile application and mobile and responsive web page testing. 00:19:21.280 --> 00:19:27.800 And it's a company that offers a service that has, like you can rent a device. 00:19:28.040 --> 00:19:36.520 So somebody, like, tells you that your website or your web application or something doesn't work on this particular device. 00:19:36.520 --> 00:19:38.360 You don't have to go out and buy it. 00:19:38.360 --> 00:19:38.740 Yeah. 00:19:38.740 --> 00:19:41.540 Android, Oreo, whatever, right? 00:19:41.540 --> 00:19:41.780 Yeah. 00:19:41.780 --> 00:19:42.500 It's on this? 00:19:42.500 --> 00:19:42.820 Yeah. 00:19:42.820 --> 00:19:49.460 You can go and rent it for, like, I think their prices are, like, 10 cents a minute or something like that. 00:19:49.460 --> 00:19:52.200 But you can – I have no idea what their prices are, actually. 00:19:52.200 --> 00:19:52.800 I can't remember. 00:19:52.800 --> 00:19:59.000 But it's a commercial product, but I want to make sure that Test and Code isn't just about open source stuff. 00:19:59.000 --> 00:20:02.200 It's also companies that are helping out that area. 00:20:02.200 --> 00:20:03.420 So it's good. 00:20:03.420 --> 00:20:03.700 Yeah. 00:20:03.700 --> 00:20:05.180 It's cool to cover the whole spectrum. 00:20:05.180 --> 00:20:10.340 And can you imagine what their data center must be like with a thousand different phones running in there? 00:20:10.340 --> 00:20:10.580 Yeah. 00:20:10.580 --> 00:20:16.040 And I also asked them silly things like, okay, so I operate my phone with my finger. 00:20:16.040 --> 00:20:19.720 Do you have somebody – are you paying somebody to move their finger or something? 00:20:19.720 --> 00:20:22.500 And they said, no, they've got that all figured out, automated. 00:20:23.300 --> 00:20:23.980 So – 00:20:23.980 --> 00:20:25.080 Perfect. 00:20:25.080 --> 00:20:25.580 Perfect. 00:20:25.580 --> 00:20:26.920 All right. 00:20:26.920 --> 00:20:29.540 Well, Brian, thanks for sharing the news this week and meeting with me. 00:20:29.540 --> 00:20:30.680 And as always, you know. 00:20:30.680 --> 00:20:30.900 Yeah. 00:20:30.900 --> 00:20:31.380 Thank you. 00:20:31.380 --> 00:20:32.220 Talk to you later. 00:20:32.220 --> 00:20:32.560 You bet. 00:20:32.560 --> 00:20:32.760 Bye. 00:20:32.760 --> 00:20:33.340 Bye, everyone. 00:20:33.340 --> 00:20:36.360 Thank you for listening to Python Bytes. 00:20:36.360 --> 00:20:38.920 Follow the show on Twitter via at Python Bytes. 00:20:38.920 --> 00:20:41.820 That's Python Bytes as in B-Y-T-E-S. 00:20:41.820 --> 00:20:45.220 And get the full show notes at Pythonbytes.fm. 00:20:45.220 --> 00:20:49.580 If you have a news item you want featured, just visit Pythonbytes.fm and send it our way. 00:20:49.580 --> 00:20:52.300 We're always on the lookout for sharing something cool. 00:20:52.780 --> 00:20:55.680 On behalf of myself and Brian Okken, this is Michael Kennedy. 00:20:55.680 --> 00:20:59.300 Thank you for listening and sharing this podcast with your friends and colleagues.