Question

What is the best (or ‘Pythonic’) way to test if a class has a specific method defined?

Both of these work but don’t feel ‘correct’ in that in the second one, I just try to access it and trap for an exception if it doesn’t exist.

Is there a better / more correct way?

class TestClass(object):
    def TestFunc(self):
        pass



if 'TestFunc' in dir(TestClass):
    print 'yes'
else:
    print 'No'



try:
    if TestClass.__getattribute__(TestClass, 'TestFunc'):
        print 'yes'

except:
    print 'No'

Answer 1

Use hasattr:

class Foo(object):
    def bar():
        pass

assert hasattr(Foo, 'bar')

If you really mean to test whether the attribute is a method, you could do this:

assert hasattr(Foo, 'bar') and callable(getattr(Foo, 'bar'))