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Should I use a class or dictionary?
...ould your __init__ code go?
Classes are for bundling related data (and usually code).
Dictionaries are for storing key-value relationships, where usually the keys are all of the same type, and all the values are also of one type. Occasionally they can be useful for bundling data when the key/attri...
What are metaclasses in Python?
...ass is an instance of a metaclass.
While in Python you can use arbitrary callables for metaclasses (like Jerub shows), the better approach is to make it an actual class itself. type is the usual metaclass in Python. type is itself a class, and it is its own type. You won't be able to recreate somet...
Usage of __slots__?
What is the purpose of __slots__ in Python — especially with respect to when I would want to use it, and when not?
11 A...
How to check size of a file using Bash?
... be an easier way to check for file sizes instead. I.e. file.txt is normally 100k; how to make a script check if it is less than 90k (including 0), and make it do wget a new copy because the file is corrupt in this case.
...
Select first row in each GROUP BY group?
...
On Oracle 9.2+ (not 8i+ as originally stated), SQL Server 2005+, PostgreSQL 8.4+, DB2, Firebird 3.0+, Teradata, Sybase, Vertica:
WITH summary AS (
SELECT p.id,
p.customer,
p.total,
ROW_NUMBER() OVER(PARTITION BY p.cus...
How do I edit an existing tag message in git?
...;tag-name> [commit]
Whole story:
Building on Sungram's answer (originally proposed as an edit):
1. Accepted answer
This is an improvement over Andy and Eric Hu's answers.
Their answers will create a new tag object that references the old tag object and both are going to have the same name. ...
Accessing class variables from a list comprehension in the class definition
...ing a newly created local namespace and the original global namespace. (Usually, the suite contains only function definitions.) When the class’s suite finishes execution, its execution frame is discarded but its local namespace is saved. [4] A class object is then created using the inheritance lis...
Is it possible to have two partial classes in different assemblies represent the same class?
...otion.so/vapolia/Secret-feature-Xamarin-Forms-control-s-auto-registration-1fd6f1b0d98d4aabb2defa0eb14961fa
It uses at its core
What are some (concrete) use-cases for metaclasses?
...a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plotting call. So to create both an interactive plotting wrapper and an offscreen plotting wrapper, I found it was more efficient to do this via metacla...
Why does += behave unexpectedly on lists?
...
The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...