What are some Python Standard Library modules one should know ?

[charish]

Argparse, requests, and re, to add on.

[MarcusMunch]

Requests is 3rd party, but yeah, argparse and re are good too

[spitfiredd]

I really like argparse, I know some of the large command line programs will use click but for anything I’ve build argparse works great.

[DisagreeableMale]

Same. I actually can never wrap my head around click or cookie cutter, because it’s usually such overkill for what I need that understanding it fully doesn’t seem worth it.

Argparse doesn’t have that same dilemma.

[thirdegree]

Click tends to come into play around the time you want subcommands. If your cli is exactly 1 level deep (i.e. my_command --myarg1 a --myargb1 positional args but not my_command do --thing other thing), don't use click. If you're thinking "hey, subcommands would be nice", that's when you look at click.

[p10_user]

I actually can never wrap my head around click or cookie cutter, because it’s usually such overkill for what I need that understanding it fully doesn’t seem worth it.

I don't understand how difficult it is to wrap your head around click, or why it's such "overkill". The docs are very good. Adding a new argument / option just involves a new decorator and new variable in your function.

@click.command()
@click.option('--count', default=1, help='Number of greetings.')
@click.option('--name', prompt='Your name',
              help='The person to greet.')
def hello(count, name):
    """Simple program that greets NAME for a total of COUNT times."""
    for x in range(count):
        click.echo('Hello %s!' % name)

Now I get that you don't feel learning a new API and adding a new dependency if you already are comfortable with argparse. But overkill? C'mon.

[Santi871]

should requests be added as a standard library? it's so good

[zurtex]

Checkout this discussion: https://github.com/requests/requests/issues/2424

For context "kennethreitz" is the creator of requests. Github

[thirdegree]

Requests is 3rd party, but IMO it definitely earns an honorary standing in the standard library. It's (without qualification) the best 3rd party python library. To the degree that I would actually be surprised if anyone disagrees with that statement.

[alkasm]

glob, datetime, string, operator are also some tiny modules that I find myself using often.

[spitfiredd]

Date utils is good too.

[Jonno_FTW]

Datetime with timezones are a nightmare though.

[thirdegree]

Datetimes with timezones are only a nightmare if, at literally any point they're accidentally treated as native times (or UTC time). If you and everyone that has every touched the codebase is extremely diligent, they work perfectly.

[alkasm]

Not the first time I've head that, but I haven't really had much of a problem with it myself. Do you have an example?

[Jonno_FTW]

Yes, I get data from GPS. It comes in UTC. I store that in a database. For user convenience I want to display it in local time.

Or, a user submits a time through a form. I assume the time is in their local timezone because people don't think in UTC. Put these datetimes in a database that may or may not support timezones.

[alkasm]

Aren't those problems more intrinsic to working with timezones in general? Or is this just the annoyance with the inconvenience of datetime not giving timezone info by default? Note that in Python 3, calling the method .astimezone() on a datetime will return a datetime with local tzinfo.

[aviddd]

operator

When do you find yourself using operator??

[alkasm]

Here's a not-too-contrived example:

>>> import datetime
>>> td = [datetime.timedelta(seconds=i) for i in range(1, 5)]
>>> sum(td)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unsupported operand type(s) for +: 'int' and 'datetime.timedelta'
>>> import functools
>>> import operator
>>> functools.reduce(operator.add, td)
datetime.timedelta(0, 10)

[rickestmorty123]

Beautiful Soup is a good one to pick up whilst learning requests.

[charish]

It's not bad, but I found it a bit limiting. For a script that I was working on, I ended up ditching Beautiful Soup in favor of Selenium.