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Why does “pip install” inside Python raise a SyntaxError?
...stalled package so this is the right way of using the API: subprocess.check_call([sys.executable, '-m', 'pip', 'install', 'SomeProject']) but since Python allows to access internal API and you know what you're using the API for you may want to use internal API anyway eg. if you're building own GUI p...
PHP mail function doesn't complete sending of e-mail
... one you need to run through the checklist below to find any potential pitfalls you may be encountering.
Make sure error reporting is enabled and set to report all errors
Error reporting is essential to rooting out bugs in your code and general errors that PHP encounters. Error reporting needs to ...
convert_tz returns null
...ving these files to a different location such as /usr/share/zoneinfo/.bak/ allows for the command
mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root -p mysql
to fully populate all of the expected timezone information.
This may or may not be a bug in my installed version of MySQL:
$ mysql -...
How do I do an OR filter in a Django query?
...
@alexis: you could also do Item.objects.filter(creator__in=creators), for example.
– Kevin London
Dec 9 '14 at 23:11
4
...
How to schedule a function to run every hour on Flask?
...om apscheduler.schedulers.background import BackgroundScheduler
def print_date_time():
print(time.strftime("%A, %d. %B %Y %I:%M:%S %p"))
scheduler = BackgroundScheduler()
scheduler.add_job(func=print_date_time, trigger="interval", seconds=3)
scheduler.start()
# Shut down the scheduler when ...
Extract elements of list at odd positions
...
Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation
The [1::2]...
How do I determine the size of an object in Python?
...turn the size of an object in bytes.
The object can be any type of object.
All built-in objects will return
correct results, but this does not
have to hold true for third-party
extensions as it is implementation
specific.
Only the memory consumption directly attributed to the object is
accounted for...
Unexpected results when working with very big integers on interpreted languages
...em will work in this case, since Python switches to long integers automatically if needed. And if that's not enough, it will switch to big integers as well.
– Alok Singhal
Aug 4 '13 at 19:37
...
What is __future__ in Python used for and how/when to use it, and how it works
__future__ frequently appears in Python modules. I do not understand what __future__ is for and how/when to use it even after reading the Python's __future__ doc .
...
Why do some functions have underscores “__” before and after the function name?
...rms using leading or trailing underscores are
recognized (these can generally be combined with any case convention):
_single_leading_underscore: weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore.
single_trailing_underscore_: ...