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How do I correctly clean up a Python object?
...it close() statement is that you have to worry about people forgetting to call it at all or forgetting to place it in a finally block to prevent a resource leak when an exception occurs.
To use the with statement, create a class with the following methods:
def __enter__(self)
def __exit__(self...
What does the “yield” keyword do?
... list, you can read its items one by one. Reading its items one by one is called iteration:
>>> mylist = [1, 2, 3]
>>> for i in mylist:
... print(i)
1
2
3
mylist is an iterable. When you use a list comprehension, you create a list, and so an iterable:
>>> mylist = [...
Sqlite or MySql? How to decide? [closed]
...
Their feature sets are not at all the same. Sqlite is an embedded database which has no network capabilities (unless you add them). So you can't use it on a network.
If you need
Network access - for example accessing from another machine;
Any real deg...
How can you set class attributes from variable arguments (kwargs) in python
...riable number of arguments and then sets them as class attributes conditionally.
10 Answers
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Python class inherits object
... so are numerous, to list some of them:
Support for descriptors. Specifically, the following constructs are made possible with descriptors:
classmethod: A method that receives the class as an implicit argument instead of the instance.
staticmethod: A method that does not receive the implicit ar...
How do I get the path and name of the file that is currently executing?
I have scripts calling other script files but I need to get the filepath of the file that is currently running within the process.
...
How to uglify output with Browserify in Gulp?
...
You actually got pretty close, except for one thing:
you need to convert the streaming vinyl file object given by source() with vinyl-buffer because gulp-uglify (and most gulp plugins) works on buffered vinyl file objects
So you...
How to get number of entries in a Lua table?
...ual, any of 3, 5 and 9 are valid results for #t. According to the manual, calling # on non-sequences is undefined. That means that any result (-1, 3, 3.14, 5, 9) is valid.
– cubuspl42
May 12 '14 at 20:08
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One DbContext per web request… why?
...the DbContext caches data, it gets stale pretty soon. This will get you in all sorts of trouble when multiple users/applications work on that database simultaneously (which is very common of course). But I expect you already know that and just want to know why not to just inject a new instance (i.e....
Find all packages installed with easy_install/pip?
Is there a way to find all Python PyPI packages that were installed with easy_install or pip? I mean, excluding everything that was/is installed with the distributions tools (in this case apt-get on Debian).
...