[ Python 常見問題 ] How to disable python warnings

Source From Here 
Question 
I am working with code that throws a lot of (for me at the moment) useless warnings using the warnings library. Reading (/scanning) the documentation I only found a way to disable warnings for single functions. But I don't want to change so much of the code. 

Is there maybe a flag like python -no-warning foo.py? 

What would you recommend? 

How-To 
For the command line, there's the -W option. 

# python -W ignore foo.py

You can also check the suppress warnings section of the python docs: 

If you are using code that you know will raise a warning, such as a deprecated function, but do not want to see the warning, then it is possible to suppress the warning using the catch_warnings context manager:

For example: 

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1. import warnings  
2.   
3. def fxn():  
4.     warnings.warn("deprecated", DeprecationWarning)  
5.   
6. with warnings.catch_warnings():  
7.     warnings.simplefilter("ignore")  
8.     fxn()  

I don't condone it, but you could just suppress all warnings with this: 

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1. import warnings  
2. warnings.filterwarnings("ignore")  

Ex: 

>>> import warnings 
>>> def f(): 
... print('before') 
... warnings.warn('you are warned!') 
... print('after') 
>>> f() 
before 
__main__:3: UserWarning: you are warned! 
after 
>>> warnings.filterwarnings("ignore") 
>>> f() 
before 
after