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Multiple levels of 'collection.defaultdict' in Python
...ng specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created.
– interjay
Oct 11 '13 at 12:53
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Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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What's the canonical way to check for type in Python?
...ation.
One more note: in this case, if you're using Python 2, you may actually want to use:
if isinstance(o, basestring):
because this will also catch Unicode strings (unicode is not a subclass of str; both str and unicode are subclasses of basestring). Note that basestring no longer exists in P...
Efficiently updating database using SQLAlchemy ORM
...ngs in mind when using the ORM and plain SQL in the same transaction. Basically, from one side, ORM data modifications will only hit the database when you flush the changes from your session. From the other side, SQL data manipulation statements don't affect the objects that are in your session.
So...
How to iterate through two lists in parallel?
...hat advantage that only itertools.izip() had in Python 2 and thus it is usually the way to go.
– Daniel S.
Jun 14 '16 at 17:40
5
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How to run functions in parallel?
...find an answer to my question. I am trying to run multiple functions in parallel in Python.
6 Answers
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Is generator.next() visible in Python 3?
...son for this is consistency: special methods like __init__() and __del__() all have double underscores (or "dunder" in the current vernacular), and .next() was one of the few exceptions to that rule. This was fixed in Python 3.0. [*]
But instead of calling g.__next__(), use next(g).
[*] There are ...
How to customize user profile when using django-allauth
I have a django project with the django-allauth app. I need to collect additional data from the user at signup. I came across a similar question here but unfortunately, no one answered the profile customization part.
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How to avoid .pyc files?
... I just tried this and, it does work for imported modules. Specifically, once this variable is set anything imported later won't generate pyc files. This is delightful. Thanks.
– user234736
Nov 22 '12 at 19:59
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Why is it string.join(list) instead of list.join(string)?
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I do not agree conceptually even if It makes sense codewise. list.join(string) appears more an object-oriented approach whereas string.join(list) sounds much more procedural to me.
– Eduardo Pignatelli
Jan 14 ...