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How do I get the object if it exists, or None if it does not exist?
...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 above and use t...
Technically, why are processes in Erlang more efficient than OS threads?
...ave the same safety properties (ECMAScript, Java, C♯, VB.NET, PHP, Perl, Python, Ruby, Clojure, Scala, Kotlin, Groovy, Ceylon, F♯, OCaml, the "Objective" part of "Objective-C", the "++" part of "C++"). If it weren't for legacy C code, and legacy features of C++ and Objective-C, we wouldn't even ...
Tying in to Django Admin's Model History
...erver.serial, server.name)
# http://dannyman.toldme.com/2010/06/30/python-list-comma-comma-and/
elif len(updated_list) > 1:
change_message = "Changed " + ", ".join(map(str, updated_list[:-1])) + " and " + updated_list[-1] + "."
else:
change_message ...
Why is it recommended to have empty line in the end of a source file?
...le. Several text editors, like Vim, and several compilers (notably C++ and Python) will issue warnings. (In C++'s case, the standard explicitly requires this.)
– greyfade
Nov 26 '16 at 8:08
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How does RegexOptions.Compiled work?
...
Thanks for your answer but your code is in the Python language. The question was about the Microsoft .NET framework RegexOptions.Compiled option. You can see the [ .net ] tag attached below the question.
– stomy
Aug 5 '19 at 17:38
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What is the difference between a deep copy and a shallow copy?
...ctions can be diverse data structures which stores multiple data items. In python we have tuple,list,dictionery,etc
– Murphy
Aug 9 '16 at 3:58
2
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Xcode build failure “Undefined symbols for architecture x86_64”
... edited Mar 19 '14 at 11:55
python
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answered Aug 24 '13 at 0:43
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How do you get a string to a character array in JavaScript?
...s also referenced as "splat" (e.g. in PHP or Ruby or as "scatter" (e.g. in Python).
Demo
Try before buy
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Pandas percentage of total with groupby
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It might, but it didn't work for me. Does pandas in Python 3 work a bit differently?
– dhardy
Feb 9 '15 at 9:59
1
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Django Template Variables and Javascript
...tation */ } in JS file and than you use it on some pages using myWidget({{ pythonConfig | js }}). But you can not use it in JS files (as you noticed), so it has its limitations.
– Yaroslav Admin
Dec 21 '17 at 16:55
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