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Django database query: How to get object by id?
Django automatically creates an id field as primary key.
6 Answers
6
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Python extending with - using super() Python 3 vs Python 2
Originally I wanted to ask this question , but then I found it was already thought of before...
5 Answers
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How do you detect where two line segments intersect? [closed]
...f r × s = 0 and (q − p) × r ≠ 0, then the two lines are parallel and non-intersecting.
If r × s ≠ 0 and 0 ≤ t ≤ 1 and 0 ≤ u ≤ 1, the two line segments meet at the point p + t r = q + u s.
Otherwise, the two line segments are not parallel but do not intersect....
How do I find the location of my Python site-packages directory?
...ib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and see python -m site --help for explanations.
Hint: Running pip list --user or pip freeze -...
Google Chrome Extensions - Can't load local images with CSS
...ion that uses the content script feature to modify a website. More specifically, the background-image of said website.
8 ...
How to count the number of set bits in a 32-bit integer?
...Hamming Weight', 'popcount' or 'sideways addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's ...
Adding information to an exception?
...essage + ' happens at %s' % arg1)
bar('arg1')
Traceback (most recent call last):
File "test.py", line 13, in <module>
bar('arg1')
File "test.py", line 11, in bar
raise type(e)(e.message + ' happens at %s' % arg1)
IOError: Stuff happens at arg1
Update 1
Here's a slight modif...
How to disable and re-enable console logging in Python?
... If you wanted to only filter message below a certain log level (say, all INFO messages), you could change the second line to something like logger.setLevel(logging.WARNING)
– Hartley Brody
Jan 5 '18 at 16:48
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static constructors in C++? I need to initialize private static objects
... to have a class with a private static data member (a vector that contains all the characters a-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables ...
How to list out all the subviews in a uiviewcontroller in iOS?
I want to list out all the subviews in a UIViewController . I tried self.view.subviews , but not all of the subviews are listed out, for instance, the subviews in the UITableViewCell are not found. Any idea?
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