[ Python 常見問題 ] Is there a way to track the number of times a function is called?

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Question
So i'm trying to make a function that keeps track how many times a method is called. for example:

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1. a = [1,2,3,4]  
2. a.pop()  

I want to know how many times a.pop() was called so far so for this example, i would get 1. Is there a way to do this?

HowTo
You could use a decorator that tracks how many times the function is called. Since list is a built-in, you can't decorate or replace its pop method so you'd have to use your own list class, for example:

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1. def counted(f):  
2.     def wrapped(*args, **kwargs):  
3.         wrapped.calls += 1  
4.         return f(*args, **kwargs)  
5.     wrapped.calls = 0  
6.     return wrapped  
7.   
8. class MyList(list):  
9.     @counted  
10.     def pop(self, *args, **kwargs):  
11.         return list.pop(self, *args, **kwargs)  
12.   
13. x = MyList([1, 2, 3, 4, 5])  
14. for i in range(3):  
15.     x.pop()  
16.   
17. print x.pop.calls # prints 3