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if A vs if A is not None:
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The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
How to len(generator()) [duplicate]
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Generators have no length, they aren't collections after all.
Generators are functions with a internal state (and fancy syntax). You can repeatedly call them to get a sequence of values, so you can use them in loop. But they don't contain any elements, so asking for the length of ...
Build an ASCII chart of the most commonly used words in a given text [closed]
... LabVIEW's very happy in its hardware control and measurement niche, but really pretty awful for string manipulation.
– Joe Z
Jul 4 '10 at 6:23
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Multiple Models in a single django ModelForm?
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But how? Usually a FormView only has a single form_class assigned to it.
– erikbwork
Oct 7 '16 at 17:42
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How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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Which characters are valid in CSS class names/selectors?
What characters/symbols are allowed within the CSS class selectors?
I know that the following characters are invalid , but what characters are valid ?
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How to clear the interpreter console?
Like most Python developers, I typically keep a console window open with the Python interpreter running to test commands, dir() stuff, help() stuff , etc.
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SQL Server - Create a copy of a database table and place it in the same database?
...a new table with the same column structure (just like he said) and inserts all data into the new table for you.
– user5855178
Apr 5 '17 at 14:14
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How to make a chain of function decorators?
...her object
scream = shout
# Notice we don't use parentheses: we are not calling the function,
# we are putting the function "shout" into the variable "scream".
# It means you can then call "shout" from "scream":
print(scream())
# outputs : 'Yes!'
# More than that, it means you can remove the old...
Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
... gcc-4.8 1.53s 1.52s -Os
In some cases you can alleviate the effect of disadvantageous optimizations by asking gcc to optimize for your particular processor (using options -mtune=native or -march=native):
Processor Compiler Time (-O2 -mtune=native) Time (-Os...