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Dynamic variable names in Bash
...Fgilrtux] [-p] [name[=value] ...]. You might double-check that you are actually running 4.x and not 3.2.
– chepner
Dec 2 '13 at 16:08
5
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TypeError: module.__init__() takes at most 2 arguments (3 given)
...named Object.py . When I try to inherit from this class in another file, calling the constructor throws an exception:
5 An...
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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Using @property versus getters and setters
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Prefer properties. It's what they're there for.
The reason is that all attributes are public in Python. Starting names with an underscore or two is just a warning that the given attribute is an implementation detail that may not stay the same in future versions of the code. It doesn't preven...
Elegant ways to support equivalence (“equality”) in Python classes
When writing custom classes it is often important to allow equivalence by means of the == and != operators. In Python, this is made possible by implementing the __eq__ and __ne__ special methods, respectively. The easiest way I've found to do this is the following method:
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Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
... the following way:
First take 2 variables: COUNTER and VALUE.
First set all registers to 0;
Every time you receive an integer I, increment COUNTER and set VALUE to max(VALUE, I);
Then send an ICMP echo request packet with data set to I to the router. Erase I and repeat.
Every time you receive the...
Length of generator output [duplicate]
... Fibonacci numbers. You can get as many Fibonacci numbers as you want by calling next().
If you really need to know the number of items there are, then you can't iterate through them linearly one time anyway, so just use a different data structure such as a regular list.
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What is the difference between old style and new style classes in Python?
...(x) is always <type
'instance'>.
This reflects the fact that all old-style instances, independently of
their class, are implemented with a single built-in type, called
instance.
New-style classes were introduced in Python 2.2 to unify the concepts of class and type.
A new-s...
Getting Django admin url for an object
...e was an easy way to get the admin url of an object, and I had written a small filter that I'd use like this: <a href="{{ object|admin_url }}" .... > ... </a>
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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 -...