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How do I get the object if it exists, or None if it does not exist?
...go will raise the DoesNotExist exception every time.
The idiomatic way to handle this in python is to wrap it in a try catch:
try:
go = SomeModel.objects.get(foo='bar')
except SomeModel.DoesNotExist:
go = None
What I did do, is to subclass models.Manager, create a safe_get like the code a...
Move all files except one
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If you use bash and have the extglob shell option set (which is usually the case):
mv ~/Linux/Old/!(Tux.png) ~/Linux/New/
share
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improve...
Storing sex (gender) in database
... 2,147,483,648 to 2,147,483,647
BIT 1 (2 if 9+ columns) 2 (0 and 1)
CHAR(1) 1 26 if case insensitive, 52 otherwise
The BIT data type can be ruled out because it only supports two possible genders which is inadequate. While INT supports more than two options, i...
OwinStartup not firing
I had the OwinStartup configuration code working perfectly and then it stopped working. Unfortunately I'm not sure exactly what I did to get it to stop working and am having a really hard time figuring it out.
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Check whether an input string contains a number in javascript
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Exactly what I needed. Thanks
– AndyH
Oct 18 '16 at 7:35
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How do I install the OpenSSL libraries on Ubuntu?
...install-openssl-manually-on-linux or howtoforge.com/tutorial/… libraries and header files are found under the same directory after installation: /usr/local/ssl
– MickaelT
Jan 22 '19 at 22:37
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how to show lines in common (reverse diff)?
...ines in common rather than the lines which are different between them. Command line unix or windows is fine.
7 Answers
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Merge / convert multiple PDF files into one PDF
...er to provide out.pdf, or else it will overwrite the last file in your command, sigh.
– mlissner
Oct 19 '13 at 22:20
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Converting a JS object to an array using jQuery
...ous, the keys don't need to be sequential (i.e. in this example they are 1 and 2 - but they could just as well be a string key or non sequential number
– Simon_Weaver
May 31 '16 at 2:41
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How do I update pip itself from inside my virtual environment?
...ng to pip --version , I currently have pip 1.1 installed in my virtualenv and I want to update to the latest version.
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