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Django database query: How to get object by id?
Django automatically creates an id field as primary key.
6 Answers
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Is there a benefit to defining a class inside another class in Python?
What I'm talking about here are nested classes. Essentially, I have two classes that I'm modeling. A DownloadManager class and a DownloadThread class. The obvious OOP concept here is composition. However, composition doesn't necessarily mean nesting, right?
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How to find the installed pandas version
...trouble with some of pandas functionalities. How do I check what is my installation version?
6 Answers
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Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
... always move from its argument. It's supposed to move if the argument is really an rvalue, and copy if it's an lvalue.
The behaviour, you observe, which always moves, is a bug in libstdc++, which is now fixed according to a comment on the question. For those curious, I took a look at the g++-4.8 he...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...t is both commutative and associative. This means the operation can be parallelized.
This distinction is very important for Big Data / MPP / distributed computing, and the entire reason why reduce even exists. The collection can be chopped up and the reduce can operate on each chunk, then the red...
Creating JS object with Object.create(null)?
...t.create(null) doesn't inherit from anything and thus has no properties at all.
In other words: A javascript object inherits from Object by default, unless you explicitly create it with null as its prototype, like: Object.create(null).
{} would instead be equivalent to Object.create(Object.prototy...
Expand Python Search Path to Other Source
.... Remember that when you distribute your project to other users, they typically install it in such a manner that the Python code files will be automatically detected by Python's importer (i.e. packages are usually installed in the site-packages directory), so if you mess with sys.path in your code, ...
Concatenating two one-dimensional NumPy arrays
...smetic than substantial, but it's good when the API is consistent (e.g. if all the numpy functions that take variable length argument lists require explicit sequences).
– Jim K.
Aug 24 '16 at 20:43
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Strip HTML from strings in Python
...those of you using newer versions of Python (3.2+) is that you'll need to call the parent class's __init__ function. See here: stackoverflow.com/questions/11061058/….
– pseudoramble
Aug 18 '13 at 17:54
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