🌐 Mailman 3 December 2019 - Python-list - python.org

on sorting things
by Eli the Bearded Dec. 19, 2019

Dec. 19, 2019

I recently saw a link to an old post on a blog and then started looking at the newer posts. This one: https://leancrew.com/all-this/2019/11/the-key-to-sorting-in-python/ discusses ways to deal with useful sorting of movie / television show titles. Some initial words should be re-ordered for sorting purposes (_Adventures of Huckleberry Finn, The_), roman numbers should sort like regular numbers (_Rocky V_ comes before _Rocky IX_), and something needs to be done about sorting accented vowels. But what caught my eye most, as someone relatively new to Python but with long experience in C in Perl, is sorting doesn't take a *comparison* function, it takes a *key generator* function, and that function is supposed to transform the thing into something that the native comparison knows how to compare. This seems a strange choice, and I'm wondering if someone can explain the benefits of doing it that way to me. Elijah ------ imagines it could make porting some code in or out of Python trickier

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Using generators in Django
by onlinejudge95 Dec. 18, 2019

Dec. 18, 2019

Hi Devs, A quick question. I am using Django to schedule some commands to populate my PostgreSQL(Apart from using it as a web framework). I am currently fetching records from a particular table and for each of those records doing some calculation and storing the processed data in some other database. The skeleton code looks like this ``` ... def fetch_needs(project_id): for item in MyNeedsModel.filter(project_id=project_id).all(): yield item ... class Command(django.core.management.base.BaseCommand): def add_argument(self, parser): ... def handler(self, *args, **kwargs): project = (args[0], args[1]) project_id = MyProject.filter(...).id for need in fetch_needs(project_id): .... ``` I need to know whether the use of generators is correct here, in the sense that would it have any performance issues. The point that I am having trouble understanding is a comment on my code review. Also don’t use generator you are bypassing django inbuilt caching > mechanism. Using integrator it will create another list and get them one by > one Any help would be appreciated. Thanks, onlinejudge95

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INHERITANCE in python3
by vahid asadi Dec. 18, 2019

Dec. 18, 2019

HI guys this is my first post on python mailing lists ever and i glad to do this. my problem here is why this attribute is not recognize by python and it raise an traceback error that said 'there is no such p.family attribute'. although i use multiple inheritance with 'super ' it not works. thanks for your help. ``` class Username: def __init__(self,name,*args): self.name = name class Userfamily: def __init__(self,family,*args): self.family = family class Person(Username,Userfamily): def __init__(self,*args): super().__init__(*args) p = Person("v","aaa")print(p.name)print(p.family)```

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Re: 3rd party mail package
by Tobiah Dec. 18, 2019

Dec. 18, 2019

On 12/14/19 1:13 AM, Barry wrote: > I guess the 2nd party is the user. I think of the user as the first party. 1) I want a thing for python. 2) Python doesn't have a very good one 3) Someone else will give it to you > Barry > >> On 13 Dec 2019, at 21:13, Abdur-Rahmaan Janhangeer <arj.python(a)gmail.com> wrote: >> >> Wonder where the 2nd party went to. Thanks will look into it! >> -- >> https://mail.python.org/mailman/listinfo/python-list >> >

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Re: strptime for different languages
by Tobiah Dec. 18, 2019

Dec. 18, 2019

> A couple of point about your code: > > 1. Don't use a bare 'except' because it'll catch _any_ exception. See > what exception strptime will raise and catch only that. I'm well aware of this, but I was too lazy to write something to generate the exception to find out what datetime would throw in this case. It crossed my mind when posting, but I was illustrating an idea rather than submitting usable code. > 2. Why use 'continue' instead of 'pass'? No reason. Does one have a benefit over the other? Tobiah

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Re: strptime for different languages
by Tobiah Dec. 18, 2019

Dec. 18, 2019

> What I tried is a cascade of try's: > > try: > d = strptime(date_string, format_string_1) > except: > try: > d = strptime(date_string, format_string_2) > except: > try: > d = strptime(date_string, format_string_3) > except: > ... This is not about dates, but for the above, I'd try: for f in (format1, format2, format3): try: d = strptime(date_string, f) except: continue else: break That way you can manipulate the content and number of the formats, or pull them from a database or whatever without having to edit your code in a messy way. Tobiah

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Re: 3rd party mail package
by Tobiah Dec. 18, 2019

Dec. 18, 2019

>> I think of the user as the first party > > But that is not what Wikipedia article you linked says. > > “ In commerce, a "third-party source" means a supplier (or service provider) who is not directly controlled by either the seller (first party) nor the customer/buyer (second party) in a business transaction.” I know. I admitted that the Wikipedia article disagreed with me, forcing me into a retraction of my previous assertion. I didn't post that link to reinforce my original argument. Tobiah

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Re: Problem Running Python
by soyeomul＠doraji.xyz Dec. 17, 2019

Dec. 17, 2019

Hello Patrick^^^ > kindly assist me through the proper download and installation procedure as I really need to start learning coding with the Python programming language. In next year 2020, Ubuntu 20.04 LTS will be released with a New Hope, i guess. At there base Python will be 3.x version. If you are startman, i recommand you to start Python 3 with Ubuntu 20.04 LTS. And Ubuntu is easy^^^ Yes Ubuntu is easy^^^ HaH Ubuntu is easy^^^ Sincerely, from Ubuntu-Python guy ;;; -- ^고맙습니다 _地平天成_ 감사합니다_^))//

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This is the email address I Believe I should email for support.
by Anthony Graziano Dec. 17, 2019

Dec. 17, 2019

When I try to uninstall python 3.8.0 to reinstall, it says that the program is currsntly running. Please help Sent from [1]Mail for Windows 10 References Visible links 1. https://go.microsoft.com/fwlink/?LinkId=550986

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strptime for different languages
by Ulrich Goebel Dec. 17, 2019

Dec. 17, 2019

Hi, I need to interpret a date string to get a datetime object. That should be done with strptime from the module datetime. But I don't know enough about the locale settings from where the date sting comes. Actually the date_string cames from different contact forms inside websites made by different content management systems. So it could be 13. Januar 1965 13. January 1965 13.01.1965 1965-01-13 or even some known other formats. What I tried is a cascade of try's: try: d = strptime(date_string, format_string_1) except: try: d = strptime(date_string, format_string_2) except: try: d = strptime(date_string, format_string_3) except: ... That works, as long the month comes as number. But how to cover name of months in different language? (Shure, it would not be possible to cover all possibilities and languages. But I know the possible languages.) Best regards Ulrich -- Ulrich Goebel Am Büchel 57, 53173 Bonn

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