How to test if a class attribute is an instance method

Question

In Python I need to efficiently and generically test whether an attribute of a class is an instance method. The inputs to the call would be the name of the attribute being check

Answer 1

This function checks if the attribute exists and then checks if the attribute is a method using the inspect module.

import inspect

def ismethod(obj, name):
    if hasattr(obj, name):
        if inspect.ismethod(getattr(obj, name)):
            return True
    return False

class Foo:
    x = 0
    def bar(self):
        pass

foo = Foo()
print ismethod(foo, "spam")
print ismethod(foo, "x")
print ismethod(foo, "bar")

Answer 2

import types

print isinstance(getattr(your_object, "your_attribute"), types.MethodType)

Answer 3

def hasmethod(obj, name):
    return hasattr(obj, name) and type(getattr(obj, name)) == types.MethodType

Answer 4

You can use the inspect module:

class A(object):
    def method_name(self):
        pass


import inspect

print inspect.ismethod(getattr(A, 'method_name')) # prints True
a = A()
print inspect.ismethod(getattr(a, 'method_name')) # prints True