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Get all related Django model objects
How can I get a list of all the model objects that have a ForeignKey pointing to an object? (Something like the delete confirmation page in the Django admin before DELETE CASCADE).
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How can I find the length of a number?
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This solution would not work with large number or small number that has more than 20 digits. eg. 1.2e+22 toString().length outputs 7
– CherylG
Oct 18 '16 at 0:52
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NPM modules won't install globally without sudo
I have just reinstalled Ubuntu 12.04 LTS, and before anything else i did these steps :
14 Answers
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What do all of Scala's symbolic operators mean?
...se of teaching, into four categories:
Keywords/reserved symbols
Automatically imported methods
Common methods
Syntactic sugars/composition
It is fortunate, then, that most categories are represented in the question:
-> // Automatically imported method
||= // Syntactic sugar
++= // Syn...
How can I add an item to a IEnumerable collection?
...s can be added. In fact, it does not necessarily represent a collection at all! For example:
IEnumerable<string> ReadLines()
{
string s;
do
{
s = Console.ReadLine();
yield return s;
} while (!string.IsNullOrEmpty(s));
}
IEnumerable<string> lines ...
Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
...o this already):
Cleanly exiting a function
Often in a function, you may allocate resources and need to exit in multiple places. Programmers can simplify their code by putting the resource cleanup code at the end of the function, and all "exit points" of the function would goto the cleanup label....
In Python, what happens when you import inside of a function? [duplicate]
...every time the function is run?
No; or rather, Python modules are essentially cached every time they are imported, so importing a second (or third, or fourth...) time doesn't actually force them to go through the whole import process again. 1
Does it import once at the beginning whether or not...
What is the purpose of the -m switch?
Could you explain to me what the difference is between calling
3 Answers
3
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Build a Basic Python Iterator
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Iterator objects in python conform to the iterator protocol, which basically means they provide two methods: __iter__() and __next__().
The __iter__ returns the iterator object and is implicitly called
at the start of loops.
The __next__() method returns the next value and is implicitly cal...
Understanding the difference between __getattr__ and __getattribute__
...oesn't explicitly manage and do that via __getattr__ method.
Python will call this method whenever you request an attribute that hasn't already been defined, so you can define what to do with it.
A classic use case:
class A(dict):
def __getattr__(self, name):
return self[name]
a = A()...