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Multiple variables in a 'with' statement?
...textlib.nested, this guarantees that a and b will have their __exit__()'s called even if C() or it's __enter__() method raises an exception.
You can also use earlier variables in later definitions (h/t Ahmad below):
with A() as a, B(a) as b, C(a, b) as c:
doSomething(a, c)
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Code Golf - π day
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Yeah, the ( operator alone allowed to shed 6 strokes!
– Dan Andreatta
Mar 18 '10 at 10:25
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Check if OneToOneField is None in Django
... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
'float' vs. 'double' precision
...cand, and an exponent.
Because of this encoding, many numbers will have small changes to allow them to be stored.
Also, the number of significant digits can change slightly since it is a binary representation, not a decimal one.
Single precision (float) gives you 23 bits of significand, 8 bits of...
Get last result in interactive Python shell
... every result with _ and its numeric value
In [1]: 10
Out[1]: 10
In [2]: 32
Out[2]: 32
In [3]: _
Out[3]: 32
In [4]: _1
Out[4]: 10
In [5]: _2
Out[5]: 32
In [6]: _1 + _2
Out[6]: 42
In [7]: _6
Out[7]: 42
And it is possible to edit ranges of lines with the %ed macro too:
In [1]: def foo():
...
How to use the pass statement?
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I really don't think this properly answers the question. Citing one possible use for something, even if it is the most common use for it, is not the same as explaining what it is for.
– Schilcote
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What's the difference between IEquatable and just overriding Object.Equals()?
...t you avoid a cast from System.Object which can make a difference if it's called frequently.
As noted on Jared Parson's blog though, you still must implement the Object overrides.
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Docker: adding a file from a parent directory
...ce it tries to do it from its same directory (tbh, just what one would normally expect). Is there any way to do the same trick in Docker Hub?
– Marcel Hernandez
Mar 25 '16 at 20:31
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In a django model custom save() method, how should you identify a new object?
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Not all models have an id attribute, i.e. a model extending another through a models.OneToOneField(OtherModel, primary_key=True). I think you need to use self.pk
– AJP
Apr 9 '13 at 10:21
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How do you run a Python script as a service in Windows?
...braries that come included with ActivePython or can be installed with pywin32 (Python for Windows extensions).
This is a basic skeleton for a simple service:
import win32serviceutil
import win32service
import win32event
import servicemanager
import socket
class AppServerSvc (win32serviceutil.Ser...