Question

It seems that an acceptable answer to the question

What is a method?

is

A method is a function that’s a member of a class.

I disagree with this.

class Foo(object):
    pass

def func():
    pass

Foo.func = func

f = Foo()

print "fine so far"
try:
    f.func()
except TypeError:
    print "whoops! func must not be a method after all"

1. Is func a member of Foo?
2. Is func a method of Foo?

I am well aware that this would work if func had a self argument. That’s obvious. I’m interested in if it’s a member of foo and in if it’s a method as presented.

Answer 1

You’re just testing it wrong:

>>> class Foo(object): pass
... 
>>> def func(self): pass
... 
>>> Foo.func = func
>>> f = Foo()
>>> f.func()
>>> 

You error of forgetting to have in the def the self argument has absolutely nothing to do with f.func “not being a method”, of course. The peculiar conceit of having the def outside the class instead of inside it (perfectly legal Python of course, but, as I say, peculiar) has nothing to do with the case either: if you forget to have a first argument (conventionally named self) in your def statements for methods, you’ll get errors in calling them, of course (a TypeError is what you get, among other cases, whenever the actual arguments specified in the call can’t match the formal arguments accepted by the def, of course).