🌐 Mailman 3 May 2023 - Python-list - python.org

Re: Tkinter docs?
by Christian Gollwitzer May 24, 2023

May 24, 2023

Am 24.05.23 um 03:18 schrieb Rob Cliffe: > I have recently started converting a large project to tkinter, starting > with zero knowledge of tkinter. (You are free to think: BAD IDEA. 😁) Welcome to the awesome world of GUI development. > I was writing a subclass of the Checkbutton class (tkinter's name > for what I call a checkbox). I needed to be able to (1) set (2) clear > (3) interrogate the checked state. This is easy to do if you associate > a "variable" with each Checkbutton instance, as seems to be usual > tkinter practice. ("variable" is not a variable in the usual sense, but > an object provided by tkinter that is linked to a GUI object (such as a > Checkbutton), so that when the GUI object changes, the value of the > "variable" changes, and vice versa.) However, I decided that I wanted to > dispense with the variable, if possible. As you found out the hard way, it is possible, but then you dive into the internals of how the widgets work - usually you don't want to know that. Also, this bit differs between Tk and Ttk widgets. > [...] lengthe description of Checkbutton internals In GUI programming, you will meet a bag of concepts that you haven't seen in sequential programming before. To make it worse, every GUI toolkit brings its own new set of concepts to the table. Maybe it is helpful to work through a Tk tutorial first. This is a good one: http://tkdocs.com/tutorial/index.html Similarly to the tutorial I would suggest to stick with the ttk widgets. Those are an "update" (> 10 years ago) to the tk widgets and are supposed to provide sensible defaults matching the users experience with native GUI elements. There are only 3 widgets where you must use a Tk widget, this is Text (for multiline formatted text entry), Canvas (for 2D drawings), and Toplevel (for new windows/ popups etc.) Christian

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Re: Tkinter docs?
by aapost May 24, 2023

May 24, 2023

On 5/23/23 21:18, Rob Cliffe wrote: > Comments, anyone? > Better yet (holds breath ...) can anyone point me towards some decent > tkinter documentation? The variables are slightly more integrated when using tcl/tk directly, python has to have the object so you can track/use them easier. And the variables are more of what is intended to track a widgets purpose, vs state stuff that is more the state of the displaying of the widget. occasionally giving tcl/tk a try directly helps, and using the official tcl/tk docs in addition to a couple other decent docs below. https://anzeljg.github.io/rin2/book2/2405/docs/tkinter/index.html https://tkdocs.com/tutorial/styles.html https://www.tcl.tk/man/tcl8.6/ https://www.tcl.tk/man/tcl8.6/TkCmd/contents.html https://www.tcl.tk/man/tcl8.6/TkLib/contents.html (this used to be some documentation that I only discovered existed recently, but most of it doesn't load and I don't know that anyone backed it up for rehosting..) https://web.archive.org/web/20200227170827/http://effbot.org/tkinterbook tk is decent for what it can do, (and it could do potentially more if you had a lifetime to dedicate to it, lol) and it's reasonably stable and not being perpetually hacked about and broken like gtk. A couple additional pointers in case these haven't been figured out yet: Running it interactively and using tab complete helps. If you are running an app you can comment out the mytk.mainloop() statement then run python -i yourtk.py to give you access to all widgets live. For navigating them, just come up with a widget naming convention that works for you in a similar vein to how tk does (like .frame.frame.label to start), i.e. main = tk.Tk() main.frame = tk.Frame() That way if you have anchored your widgets to something at the root level you can navigate down to whatever you are looking for easily. (you can also use winfo_children() iteratively to travel the way tcl structures them, but that is tedious).

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where is requests
by Rich Osborne May 24, 2023

May 24, 2023

I have install Python 3.11.3 but my import requests does not work. I found documentation that refers to C:\python35 but I am on 3.11.3. Where do I find requests? Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows

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Re: Addition of a .= operator
by Chris Angelico May 23, 2023

May 23, 2023

On Wed, 24 May 2023 at 08:57, Rob Cliffe <rob.cliffe(a)btinternet.com> wrote: > > Do you mean "ASCII or UTF-8"? Because decoding as UTF-8 is fine with > > ASCII (it's a superset). You should always consistently get the same > > data type (bytes or text) based on the library you're using. > > > > ChrisA > OK, bad example. The point remains: condensing each step to a single > chained function can come unstuck when one of the steps needs to be made > more complicated for some reason. That's fair. Still, I wouldn't over-complicate a piece of code "just in case" it needs to become more complicated in the future. I'd rather code to what's needed now, and if that's a simple "decode as UTF-8", that's great; maybe in the future I need to cope with an insane system like "decode line by line, attempting UTF-8 first and falling back on Windows-1252, then rejoin the lines", and that's the time to implement that. (Yes, I have had to do that. Although I think I cheated and used ISO-8859-1 instead. It was a lot easier and I didn't really care about precise handling, so long as MOST things were readable.) ChrisA

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Is there a Python module to parse a date like the 'date' command in Linux?
by Chris Green May 23, 2023

May 23, 2023

I'm converting a bash script to python as it has become rather clumsy in bash. However I have hit a problem with converting dates, the bash script has:- dat=$(date --date "$1" +"%Y/%m/%d") and this will accept almost anything reasonably sensible that can be interpreted as a date, in particular it accepts things like "tomorrow", "yesterday" and "next thursday". Is there anything similar in Python or would I be better off simply using os.system() to run date from the python program? -- Chris Green ·

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Re: What to use instead of nntplib?
by Jon Ribbens May 22, 2023

May 22, 2023

On 2023-05-22, Skip Montanaro <skip.montanaro(a)gmail.com> wrote: >> My understanding is that nntplib isn't being erased from reality, >> it's merely being removed from the set of modules that are provided >> by default. >> >> I presume that once it's removed from the core, it will still be >> possible to install it via pip or some other mechanism. > > It won't magically be available via pip unless someone steps up to maintain > it as a PyPI package That would appear to have already happened over a month ago.

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Re: What to use instead of nntplib?
by Retrograde May 22, 2023

May 22, 2023

> >> See PEP 594: https://peps.python.org/pep-0594/ > > > > Thanks Cameron. > > A scary list; I must have a dozen projects from the late 90s still > > live that are using many of these! I'm glad I'm retired and won't > > be the one who has to fix 'em :-) > > It has been pointed out to me that Perl still has a supported NNTP > library. That stung. However, it's a CPAN module, which is more > equivalent to PyPI than to the standard library, so I guess that it > isn't as bad a loss of face as I feared. I'm latching onto this thread just so I can bitch: I always thought "Batteries included" was a great concept, a great philosophy, a great slogan. It encouraged me to look into python because they made the tools available for you to do just about anything they want. Who ever came up with "Removing dead batteries" as a slogan, when some of those batteries still work perfectly well, needs to rethink it. Go ahead and remove code that no longer works, OK. But removing unpopular modules? That undercuts the entire philosophy of the platform, in my opinion.

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Create Statically linked python library
by Guenther Sohler May 21, 2023

May 21, 2023

Right now my application links python dynamically. That means ldd will show something like libpython3.11.so.1.0 => /lib64/libpython3.11.so.1.0 (0x00007fd63c600000) but i dont like this dependency. ii want to link in python statically. I'd like to get a file like libpython3.11.a or similar. For that I have found https://wiki.python.org/moin/BuildStatically It describes how to compile python interpreter statically and it only contains view libs But I;d like to get a libpython3.11.a instead. How can i get this ? Thank you

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Re: Addition of a .= operator
by Greg Ewing May 21, 2023

May 21, 2023

On 21/05/23 9:18 am, Richard Damon wrote: > This just can't happen (as far as I can figure) for .= unless the object > is defining something weird for the inplace version of the operation, Indeed. There are clear use cases for overriding +=, but it's hard to think of one for this. So it would just be syntactic sugar, which is harder to justify. -- Greg

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Error installing packages or upgrading pip
by Test Only May 20, 2023

May 20, 2023

Hi there, I hope you are in a great health I am having a problem with python even though I uninstall and reinstall it again multiple times the error I get when I try to upgrade or install a package for example pip install requests I get this error which I could not find a solution for pip install requests Requirement already satisfied: requests in c:\users\uly\appdata\local\programs\python\python310\lib\site-packages\requests-2.30.0-py3.10.egg (2.30.0) WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/charset-normalizer/ WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/charset-normalizer/ WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/charset-normalizer/ WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/charset-normalizer/ WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/charset-normalizer/ WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/requests/ WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/requests/ WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/requests/ WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/requests/ WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ProtocolError('Connection aborted.', FileNotFoundError(2, 'No such file or directory'))': /simple/requests/ ERROR: Could not find a version that satisfies the requirement charset_normalizer<4,>=2 (from requests) (from versions: none) ERROR: No matching distribution found for charset_normalizer<4,>=2 WARNING: There was an error checking the latest version of pip.

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