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Create a “with” block on several context managers? [duplicate]
...rite:
with A() as X, B() as Y, C() as Z:
do_something()
This is normally the best method to use, but if you have an unknown-length list of context managers you'll need one of the below methods.
In Python 3.3, you can enter an unknown-length list of context managers by using contextlib.Exit...
Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
How to think in data stores instead of databases?
...
The datastore makes no distinction between inserts and updates. When you call put() on an entity, that entity gets stored to the datastore with its unique key, and anything that has that key gets overwritten. Basically, each entity kind in the datastore acts like an enormous map or sorted list.
Que...
Changing the image source using jQuery
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Yes. This finally did the trick. .destroy() doesn't go nearly far enough. Nuking all the html and than init again actually works when swapping out images of various sizes and such.
– Matt J.
Apr 11 '...
urllib2.HTTPError: HTTP Error 403: Forbidden
...Error, e:
print e.fp.read()
content = page.read()
print content
Actually, it works with just this one additional header:
'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
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What is the best way to ensure only one instance of a Bash script is running? [duplicate]
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If the script is the same across all users, you can use a lockfile approach. If you acquire the lock, proceed else show a message and exit.
As an example:
[Terminal #1] $ lockfile -r 0 /tmp/the.lock
[Terminal #1] $
[Terminal #2] $ lockfile -r 0 /tmp/the....
How to clear MemoryCache?
...clear it first. What is the quickest way to do this? Should I loop through all the items and remove them one at a time or is there a better way?
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Programmatically retrieve memory usage on iPhone
...trieve the amount of memory my iPhone app is using at anytime, programmatically. Yes I'm aware about ObjectAlloc/Leaks. I'm not interested in those, only to know if it's possible to write some code and get the amount of bytes being used and report it via NSLog.
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Why is it impossible to override a getter-only property and add a setter? [closed]
Why is the following C# code not allowed:
16 Answers
16
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How to enumerate an object's properties in Python?
...oes not return dynamic members (i.e., object attributes and methods dynamically defined by that object's __getattr__() method or similar magic). In all likelihood, your desired file.ImplementationName property is defined dynamically and hence not available to vars() or dir().
–...