What is the advantage of using static methods in Python?

Curious2learn picture Curious2learn · Mar 13, 2010 · Viewed 42.6k times · Source

I ran into unbound method error in python with the code

import random

class Sample(object):
'''This class defines various methods related to the sample'''

    def drawSample(samplesize,List):
        sample=random.sample(List,samplesize)
        return sample

Choices=range(100)
print Sample.drawSample(5,Choices)

After reading many helpful posts here, I figured how I could add @staticmethod above to get the code working. I am a python newbie. Can someone please explain why one would want to define static methods? Or, why are not all methods defined as static methods?

Answer

zanetu picture zanetu · Mar 23, 2014

See this article for detailed explanation.

TL;DR

1.It eliminates the use of self argument.

2.It reduces memory usage because Python doesn't have to instantiate a bound-method for each object instiantiated:

>>>RandomClass().regular_method is RandomClass().regular_method
False
>>>RandomClass().static_method is RandomClass().static_method
True
>>>RandomClass.static_method is RandomClass().static_method
True

3.It improves code readability, signifying that the method does not depend on state of the object itself.

4.It allows for method overriding in that if the method were defined at the module-level (i.e. outside the class) a subclass would not be able to override that method.