Mailman 3 June 2018 - Edu-sig

a short essay about programming
by kirby urner 08 Dec '22

08 Dec '22

A common "error" (not too serious) that I see in beginning Python (and no doubt other languages, but Python is the one I'm teaching), is having a while condition that appears to put a lid on things, but then the flow all leaks away through break statements, such that the "front door" condition is never revisited. while guess != secret: guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") break else: print("Nope, try again...") What's messed up about the above code is you never really go back to the top in the case where you'd get to leave. Rather, you exit by the back door, through break. So in that case, wouldn't have been simpler and more elegant, even more "correct" (dare I say it) to have gone: while True: # no ifs ands or buts guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") break else: print("Nope, try again...") I see lots of heads nodding, and that could be the end of the matter, but then a next question arises: wouldn't this also be a more correct solution?: while guess != secret: guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") continue # instead of break else: print("Nope, try again...") We're back to having a variable while condition, not a boolean constant, but this time we actually exit by means of it, thanks to continue or... while guess != secret: guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") else: print("Nope, try again...") ... thanks to no continue. This last one is getting a thumbs up, but then I'd pause here and say "continue" can be easier on the eyes. It's unambiguous where it takes you, in contrast to having to scan on down the gauntlet, looking for possibly other open doors. "What happens next" should not require scanning ahead too far. Help us not to get lost. Be a civic-minded coder. I'm thinking of a programming style that advises two things: (a) if you use a while condition that's variable, that's expected to change, then your goal should be to always exit because of that, i.e. that should be your only exit point. Even if some other criterion suggests exiting, you have the option to flip that "lid" at the top, to crack that front door, and bounce the ball out. (b) which is why 'continue' is your friend. You are showing the user where your 'break' statements are, except you don't use "break" statements, as you've given a non-constant condition, and your aim is to make that your ONLY exit point. In short: never use break to exit a while loop unless your condition is while True. Instead, always flip the condition and exit through the font door. However, as soon as I make that rule I can think of good reasons to break it. The other programmers in the room are shaking their heads. Won't we lose information, needed elsewhere in the program, if we "artificially" force a True condition to False. Aren't we, in effect, lying? That concern could be addressed. Keep all the info true, just treat the "lid condition" (it "keeps a lid on it") as a flag. Go ahead and remember the user's guess. allowed = 5 tries = 1 exit = False while not exit: # no other way out guess = int(input("Guess?: ") if guess == secret: print("You guessed it!") exit = True # instead of break continue print("Nope, try again...") tries += 1 if tries == allowed: print("You've maxed out") exit = True continue I think we all understand the main issue: writing reader-friendly code, and rules for doing so. There's something comforting about approaching a while loop and knowing its not a leaky sieve, riddled with back doors, maybe even an exit( ) time bomb. But in the recursion world we want a minimum of two exits usually: when another round is called for versus when we've "hit bottom". Can we have it both ways? Conclusions: Lets not be too hasty with rules of thumb and: Lets keep the reader in mind when writing code. Just because the interpreter knows to compute the flow unambiguously, doesn't mean all ways of writing it are equally reader-friendly. What may seem a gratuitous gesture, an unnecessary flourish, may actually promote reader comprehension of your code, and that should be a goal as much as satisfying the interpreter. Kirby

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MineCraft with Python
by Jurgis Pralgauskis 04 Dec '22

04 Dec '22

Hi, intro: many kids like MineCraft :) probably you know/heared of MineCraft Pi https://www.raspberrypi.org/learning/getting-started-with-minecraft-pi/ But there seems to be Py for real MC http://coderdojotc.readthedocs.io/projects/python-minecraft/en/latest/ http://www.instructables.com/id/Python-coding-for-Minecraft/ PS.: a nice article (from js4MC world) https://github.com/walterhiggins/ScriptCraft/blob/master/docs/YoungPersonsG… -- Jurgis Pralgauskis tel: 8-616 77613; Don't worry, be happy and make things better ;) http://galvosukykla.lt

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turtle coordinates: Y increase downards - as in most graphics API?
by Jurgis Pralgauskis 02 Jul '18

02 Jul '18

Hi, usually in computer graphics Y is counted to increase downwards. I casn do it with: setworldcoordinates(0, 400, 600, 0) but then, "right(..)" turns to the left :/ I could swap: right, left = left, right but on errror I get a bit misleading message >>> right() Traceback (most recent call last): File "<pyshell#10>", line 1, in <module> right() TypeError: left() takes exactly 1 argument (0 given) I thought to make this hack for kids, so better clearer error msgs... Any Ideas? Thanks :) -- Jurgis Pralgauskis tel: 8-616 77613; Don't worry, be happy and make things better ;) http://galvosukykla.lt

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creative unplugged activities in computer science classes
by mw＠creative-informatics.de 25 Jun '18

25 Jun '18

Dear Python educators, teaching Python includes explaining technical facets of the programming language and initiating and scaffolding hands-on programming exercises. However, especially if the object of the course is to develop “computational thinking” and to get a deeper understanding what computer science is, the curriculum might contain “unplugged” activities without a computer. What do you think about unplugged activities challenging creativity? I would like to advertise a questionnaire, which is part of an international study on this type of activities in computer science education. <https://goo.gl/forms/seYGUlsKHxyiqqnX2> https://goo.gl/forms/seYGUlsKHxyiqqnX2 The results will be presented in August 2018 at Constructionism in Vilnius (Lithuania) and will be available to everyone http://www.constructionism2018.fsf.vu.lt/ . Thank you and best wishes Michael Dr. Michael Weigend Fröbelstraße 68 58454 Witten Phone +49 (0)2302 60585 Mobile +49 (0)177 565 2693 http://creative-informatics.de mw(a)creative-informatics.de

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Re: [Edu-sig] turtle coordinates: Y increase downards - as in most graphics API?
by Sergio Rojas 19 Jun '18

19 Jun '18

From: kirby urner <kirby.urner(a)gmail.com> > Regarding coordinate systems, I'm probably the only teacher to > use what I call Quadrays in the classroom. ... ... > I tell them this is what Martians use, acknowledging this is > purely science fiction, Kirby, Looking way far in the back of my head, the closest thing (to the inspirational drawings of your notebook) I could recover is what is called fundamental lattice structures of solid state physics. Not sure, but in there they might use your coordinate system to better describe structures of crystals. The book by Kittel, pg 27 of the 8th Edition, has some stuff on it. Other object in that sense is the Quaternion thing https://en.wikipedia.org/wiki/Quaternion Better stop here, I am getting hurt ... Sergio Check out the free first draft of the book: Prealgebra via Python Programming https://www.researchgate.net/publication/325473565 https://github.com/rojassergio/Prealgebra-via-Python-Programming ---------------------------------------------------------------------- Message: 1 Date: Tue, 19 Jun 2018 09:05:50 -0700 From: kirby urner <kirby.urner(a)gmail.com> To: "edu-sig(a)python.org" <edu-sig(a)python.org> Subject: Re: [Edu-sig] turtle coordinates: Y increase downards - as in most graphics API? Message-ID: <CAPJgG3Qn_oLs5LFhznrdv-25K51xB=Y8gf-zrj6Xid=aPnitiQ(a)mail.gmail.com> Content-Type: text/plain; charset="utf-8" On Tue, Jun 19, 2018 at 7:27 AM, Sergio Rojas <sergio_r(a)mail.com> wrote: > > > Some issues to keep in mind: > > From the The Feynman Lectures on Physics: > > http://www.feynmanlectures.caltech.edu/I_52.html[http://www.feynmanlectures… > """ > Fig. 52?1(b)! The first molecule, the one that comes from the living > thing, is called L-alanine. The other one, which is the same chemically, > in that it has the same kinds of atoms and the same connections of the > atoms, is a ?right-hand? molecule, compared with the ?left-hand? > L-alanine, and it is called D-alanine. > ... > ... > So it looks as though the phenomena of life permit a distinction between > "right" and "left," ... > """ > > ?Yes, a very excellent suggestion and apropos in this context, Sergio. The Feynman piece is fascinating. I like that he features a "Martian" (see below). Congruent vs. Chiral: I hang out on some math teacher web groups (mostly on Facebook) and one topic that comes up a lot is "congruence". Interestingly, the math concept of "congruence" teaches us to overlook or ignore "chirality" or handedness in structures, despite these enantiomers having completely different chemical properties.? We would say the left hand is congruent to the right hand in a math class. I downloaded the PDF of your book and am reading it. Impressive! Mixing math and programming and deriving the benefits of synergy has been one of my themes as well. Regarding coordinate systems, I'm probably the only teacher to use what I call Quadrays in the classroom. Indeed, next week I'll be sharing a summer camp course in "Martian Math" with some Silicon Forest kids that features this alternative coordinate system, with four basis rays from the center of a regular tetrahedron to its four corners, using positive 4-tuples. All points in space are linear combinations of these four basis vectors. I have Python code for converting back and forth to XYZ. The centers of closest packed spheres in the CCP all have positive whole number coordinates. https://en.wikipedia.org/wiki/Quadray_coordinates[https://en.wikipedia.org/… https://github.com/4dsolutions/Python5/blob/master/Generating%20the%20FCC.i… I tell them this is what Martians use, acknowledging this is purely science fiction, and suggest that comparing and contrasting a conventional apparatus with something alien (unfamiliar) actually helps students achieve a deeper understanding of the convention. Martians also use triangles and tetrahedrons to model 2nd and 3rd powering such that 3 x 3 x 3 is a tetrahedron of 27, not a cube of 27. We have a constant for going back and forth between XYZ cubic volumes and IVM tetra volumes. http://www.4dsolutions.net/satacad/martianmath/toc.html[http://www.4dsoluti… (from my previous iteration of this class) > Other Related links: > https://phys.org/news/2014-10-handedness-life.html[https://phys.org/news/20… > http://www.iflscience.com/space/why-life-left-handed-answer-stars/[http://w… > > ?Yes very useful. Looking for chemical signatures in space leads me to Harold Kroto's discovery of C60 and its subsequent analysis and synthesis as a topic. https://youtu.be/yZ8JDDnyxC4[https://youtu.be/yZ8JDDnyxC4] (another link re chirality) Thanks again! Kirby ? > Sergio > Check out the free first draft of the book: > Prealgebra via Python Programming > https://www.researchgate.net/publication/325473565[https://www.researchgate… > https://github.com/rojassergio/Prealgebra-via-Python-Programming[https://gi… > _______________________________________________ >

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Re: [Edu-sig] turtle coordinates: Y increase downards - as in most graphics API?
by Sergio Rojas 19 Jun '18

19 Jun '18

> From: Kevin Cole <kevin.cole(a)novawebdevelopment.org> > In spite of the common "in computer graphics Y goes down", does that make > sense to new learners? I've gotten used to various coordinate systems, but > the first time I had to work with graph paper and plotting (and, for that > matter, maps) one goes "up" ("north", "forward") for Y. ... ... > From: kirby urner <kirby.urner(a)gmail.com> > This arrangement of two numbered lines considered "most normal" i.e. this > schema is rather ubiquitous and must be considered something of a home base > in classroom projects. ... > However if you walk around to the back and look from the other side... my > right is your left and so on -- these are terms relative to a point of > view, not to the object in front of us, which is where the confusion often > begins. Who's left? > Stage left means what again? It's the actor's left, not the audience's > left. ... > Math texts don't believe in talking about an observer for some reason, or > multiple observers. I expect the influence of computer science to be a > positive influence in helping address that blind spot over time. Perhaps teachers of physics could be called to make appreciations in their courses about the relativeness (in most cases) on chosen a coordinate system: right or left-handed or whatever helps to make computations simple (but not simpler). Some issues to keep in mind: >From the The Feynman Lectures on Physics: http://www.feynmanlectures.caltech.edu/I_52.html """ Fig. 52–1(b)! The first molecule, the one that comes from the living thing, is called L-alanine. The other one, which is the same chemically, in that it has the same kinds of atoms and the same connections of the atoms, is a “right-hand” molecule, compared with the “left-hand” L-alanine, and it is called D-alanine. ... ... So it looks as though the phenomena of life permit a distinction between "right" and "left," ... """ Other Related links: https://phys.org/news/2014-10-handedness-life.html http://www.iflscience.com/space/why-life-left-handed-answer-stars/ Sergio Check out the free first draft of the book: Prealgebra via Python Programming https://www.researchgate.net/publication/325473565 https://github.com/rojassergio/Prealgebra-via-Python-Programming

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Collaboratively developing OER Python textbooks.
by Jeff Elkner 18 Jun '18

18 Jun '18

Hi Sergio, I would be delighted to see this mailing list be used for collaboration and discussion around OER learning materials for Python. I'm working on remixing a wonderful textbook written for use with the College Board's AP CS Principles course: http://www.openbookproject.net/books/StudentCSP/ I've got the project on Gitlab at: https://gitlab.com/jelkner/StudentCSP Since students are the final judges of the effectiveness of education resources, I involve my students as testers / reviewers using issues tracking on Gitlab as the way for them to provide feedback. Shushantika Barua (cc'd here) proved an excellent proof reader / editor / tester. Taking a look at the issues she filed shows the process: https://gitlab.com/jelkner/StudentCSP/issues?scope=all&utf8=%E2%9C%93&state… I have a friend and colleague, Isaac Zawolo (cc'd here) who teaches math at my school. We have been talking about integrating the learning of math and computer programming for several years. We also have a large community of first language Spanish speakers at our school. So, Sergio, if you are interested, I would be glad to get my students involved in testing and contributing to both https://github.com/rojassergio/Prealgebra-via-Python-Programming and https://github.com/rojassergio/Aprendiendo-a-programar-en-Python-con-mi-com…. Let me know when you feel you have something ready for testing. Thanks! Jeff Elkner Arlington Career Center, Arlington, VA Let's work together to create a just and sustainable world! ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On June 11, 2018 9:35 AM, Sergio Rojas <sergio_r(a)mail.com> wrote: > > > On 10/05/18 16:15, Jeff Elkner wrote: > > > Dear edu-sig friends, > > > > We had an interesting discussion at the Education Summit today at > > > > Pycon about ways to better engage folks between Pycons. > > Hi Jeff, > > Are the documents of the Pycon Education Summit available on the Internet? > > > As a public school teacher, I have a particular interest in python in > > > > k12 institutions > > How are you using Python in teaching and learning? > > I finished a first crude draft of a book devoted mostly to Mathematics > > (Prealgebra topics ) via Python > > https://github.com/rojassergio/Prealgebra-via-Python-Programming ) > > which I want to improve (in content and readability) > > and perhaps the discussions of the Educational Summit > > could be of help to better shape the book on the content of topics. > > Regards, > > Sergio > > > > > > > --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > > Message: 1 > > Date: Thu, 10 May 2018 17:15:28 -0400 > > From: Jeff Elkner jeff(a)elkner.net > > To: "edu-sig(a)python.org" edu-sig(a)python.org > > Subject: [Edu-sig] What do folks think of creating a #python-k12 > > channel on freenode? > > Message-ID: > > VZIaifBvT3x43c5hYiGYuuBbco2UUmLN6mSTAcaJvyV50_KvaE9i64p83woqKoK5HY4A0zqNzpiolNsAxlMugEqQzt8I8C45aoT9XFpekS4=(a)elkner.net > > Content-Type: text/plain; charset="utf-8" > > Dear edu-sig friends, > > We had an interesting discussion at the Education Summit today at > > Pycon about ways to better engage folks between Pycons. > > As a public school teacher, I have a particular interest in python in > > k12 institutions, and in addition to posting more often on this list, > > I am considering setting up an irc channel on freenode (#python-k12 ?) > > Edu-sig mailing list > > Edu-sig(a)python.org > > https://mail.python.org/mailman/listinfo/edu-sig

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Re: [Edu-sig] On the Education Summit at Pycon
by Sergio Rojas 11 Jun '18

11 Jun '18

On 10/05/18 16:15, Jeff Elkner wrote: > Dear edu-sig friends, > > We had an interesting discussion at the Education Summit today at > Pycon about ways to better engage folks between Pycons. > Hi Jeff, Are the documents of the Pycon Education Summit available on the Internet? > As a public school teacher, I have a particular interest in python in > k12 institutions How are you using Python in teaching and learning? I finished a first crude draft of a book devoted mostly to Mathematics (Prealgebra topics ) via Python https://github.com/rojassergio/Prealgebra-via-Python-Programming ) which I want to improve (in content and readability) and perhaps the discussions of the Educational Summit could be of help to better shape the book on the content of topics. Regards, Sergio ---------------------------------------------------------------------- Message: 1 Date: Thu, 10 May 2018 17:15:28 -0400 From: Jeff Elkner <jeff(a)elkner.net> To: "edu-sig(a)python.org" <edu-sig(a)python.org> Subject: [Edu-sig] What do folks think of creating a #python-k12 channel on freenode? Message-ID: <VZIaifBvT3x43c5hYiGYuuBbco2UUmLN6mSTAcaJvyV50_KvaE9i64p83woqKoK5HY4A0zqNzpiolNsAxlMugEqQzt8I8C45aoT9XFpekS4=(a)elkner.net> Content-Type: text/plain; charset="utf-8" Dear edu-sig friends, We had an interesting discussion at the Education Summit today at Pycon about ways to better engage folks between Pycons. As a public school teacher, I have a particular interest in python in k12 institutions, and in addition to posting more often on this list, I am considering setting up an irc channel on freenode (#python-k12 ?)

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generators in the field...
by kirby urner 09 Jun '18

09 Jun '18

Wes asked (a couple posts back): is a generator a type of callable? Those copy/deepcopy links were helpful, I hope to any Python students trekking through here. edu-sig is a great climb for those into learning curves. Most definitely a generator is a "callable" as, in my Python for Kids (not a trademark [nTM]), a callable is simply "something with a mouth" where "a mouth" is an open-closed paren, with or without arguments. In a course or presentation, one might go into "emoticons" here, as distinct from emoji, coming before emoji in the evolution e.g. :-D and :-( were part of "ascii email" early on (SMTP etc.). In this older emoticon language, :-() shows "()" as a "mouth" i.e. parens are lips, and a callable is "that which may have a mouth" in this sense (albeit a sideways one). The rule "no keyword is a callable" is the same as saying, no keyword has a mouth. There's no True() or if() and print() is not a keyword (used to be, in older Pythons). print is a function, and as such is a callable. Generator function: >>> new_gen = pi() # returns digits of pi [1] >>> next(new_gen) 3 >>> next(new_gen) 1 >>> next(new_gen) 4 >>> next(new_gen) 1 >>> next(new_gen) 9 ... One of my favorite decorators comes from a David Beazely Youtube I watched where he goes something like: def nudge(f): "nudger" def started(): g = f() g.send(None) # or next(g) -- goes to first yield and waits return g return started What this does is take a generator object at define time and replace it with a proxy wherein it has already been "nudged" to the first yield, and is now waiting to be fed to next() or to have send() fire, which will at this point, after nudging, have a corresponding yield queued up to receive whatever. As ya'll recall, a generator on birth has its execution pointer still at the top, no steps taken, and the first next or send(None) takes it to the first yield, where it may output, and then "waits" (actually suspends execution and returns control to the caller thread). next(gen) always means: take steps to the next yield, or: raise a StopIteration if hitting return or falling off the end. In other words, at birth, a generator is not ready for any substantive obj.send(arg) because it's not at a yield yet. nudge (above) takes care of that for us, returning a proxy generator with "its pump already primed" so to speak, g.send(None) having taken g to the first yield already. In action: @nudge def get_mail(): "Get mail!" pickup = "nothing yet..." while True: pickup = (yield "Thank you for sending me {}".format(pickup)) if pickup == "q": break gm = get_mail() # a generator function try: while True: email = input("What to send? (q to quit): ") output = gm.send(email) print(output) except StopIteration: print("We appreciate your business") RUNTIME: What to send? (q to quit): birthday card Thank you for sending me birthday card What to send? (q to quit): postcard Thank you for sending me postcard What to send? (q to quit): q We appreciate your business Note: David Beazely is not in favor of having having a single yield both output and take input, as above, regarding such a double-duty yield as too confusing. My code might count as demented in his book. One of my favorite use of the generator-with-send ability patterns is what I call Tractor in a Farm [nTM]. Farm(ville) is an n x m array of dots or other character, could be numbers, and a Tractor is an iterator following some raster pattern, of row: each column, next row: each column and so on. When it finishes row 0 it jumps to the start of row 1, so not really a tractor -- more like how people read these left-to-right languages (like you're reading now). If the field were a cylinder, with East and West connecting, the tractor would go in a North to South spiral. At the bottom right, a Tractor starts over at the top left (so a donut?). Change in [row][column] (position) is what next() has the tractor do (there's a __next__ method). But then "fuel level" is dropping with each advance in some models, and without the occasional "send" of more fuel, the tractor will come to a grinding halt in the middle of a field somewhere (demented, but good for learning purposes). What's useful about this pattern is it's all "ASCII art" or "Unicode art" at first, but yet gives the idea of "pixels" (row, column) and therefore "pixel depth" (the bits needed to define a character), so the transition to a discussion of binary files, say with R, G, B layers, is pretty easy. The iterator : iterable relationship, between Tractor(s) : Field is pretty intuitive also, owing to the extended metaphor. The tractor is even simpler than the turtle concept deriving from Logo, as the tractor has a fixed and closed path. Finally, said tractors have a "read" and "write" verbs, or "sense" and "plant", meaning they're able to "write" to whatever cell (patch of Field) they're in (over), replacing the current character with another if need be, according to whatever rule. In Pythonic Andragogy slides, a TextWriterTractor (subclass of Tractor) starts writing a user-provided phrase at whatever initially passed-in (x,y) position in the field. Example: Just Use It. A CropCircleTractor (another subclass) reads the Field as complex numbers and plants "@" where z = z * z + current(row, column) doesn't spiral out after n iterations. Result: A Mandelbrot Set. https://flic.kr/p/9AWnC2 (results of plowing) Pythonic Andragogy slides: http://4dsolutions.net/presentations/pycon2013.pdf (not saying "not for kids") An ongoing theme: http://opensourcebridge.org/proposals/1102 Kirby [1] https://github.com/4dsolutions/Python5/blob/master/Pi%20Day%20Fun.ipynb (see last code cell for mysterious Pi generator discussed here on edu-sig in chapters past)

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another perennial topic... callable functions versus types
by kirby urner 08 Jun '18

08 Jun '18

I enjoyed our discussion of post-its versus buckets, or not versus: objects in memory take up space, and so are bucket-like, but look how many labels (post-its) some of them have! I find it useful to have memory take shape as something finite, even when we're enjoying more of it on contemporary devices. Python is biased against making gratuitous copies, or against copying gratuitously, we maybe could say. Memory is respected. L.sort() is "in place" whereas sorted(L) leaves L untouched. This "inplace" idea carries forward as a keyword argument (named parameter) in many cases. I confess, in my own courses, I could do more with deepcopy, explaining what it is and how to do it. I'll get on it. When is it a copy, when a view? is a discussion in pandas as well. Another topic: Another pair of categories I like to tease apart are function versus type, when it comes to what's a callable. range() used to be a function that returned a list. Now it returns an instance of the range type, a sequence. More like dict(), int() and so on. Not like hex(). enumerate() and zip() are likewise calls to classes, triggers to __init__s (birth methods). We're asking for instances. We're calling types. Functions return objects too, so one should not say the difference is whether they return objects. Both do. The difference is instances of a type live on with the methods of that type, whereas a function does not directly bequeath its methods to any "children". Functions are factories of other than instances of themselves, even if they return other functions. What nuances this view is that FunctionType is a type of object, so calling a function is calling a type. However, the way a function responds to being called is like an instance does when its type has a __call__ method defined. === One of my favorite ways to connect classes and functions is to show how a class might "eat" a function such that the function remains callable, and yet the instances may also multiply, in which case the functions compose to create other functions: @Composable # class def F(x): return x + 2 @Composable # class def G(x): return 2 * x H = F * F * F * G * G (H is now a "pipeline" of F(F(F(G(G(x))))) ) More on REPL.it: https://repl.it/@kurner/Composing-Functions (red X warning flag next to lambda expression is bogus, runs fine, Spyder is smarter) Kirby PS: this morning I saw Guido's talk at Stanford on type annotations, which he recently tweeted about [1]. I definitely include mentioning to be on the lookout for such syntax going forward, and not being thrown by it. I emphasize that standard core Python sees annotations more as a type of documentation, with 3rd party hooks understanding them more as directives. [1] https://twitter.com/gvanrossum/status/1003792557652914177 (June 4)

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