Hi! I think this behaviour is bug. Lets concider the following code:

import inspect
class X(object):
    def a(self):pass
    def b(self):pass
    def c(self):pass

print(inspect.getmembers(X, predicate=inspect.ismethod))
print(inspect.getmembers(X, predicate=inspect.isfunction))

In python 2.7, the results are:
[('a', <unbound method X.a>), ('b', <unbound method X.b>), ('c', <unbound method X.c>)]
[]

and in Python 3.2:
[]
[('a', <function a at 0x1b0fd10>), ('b', <function b at 0x1b0fe20>), ('c', <function c at 0x1b160d8>)]

I think, the results from python 2.7 are correct.

I think that's expected and by design.  In Python 3 there are no unbound methods, but simply functions:
>>> class X:
...   def add(a, b): return a+b
... 
>>> add = X.add
>>> add
<function add at 0xb740d26c>
>>> add(3, 4)
7
>>> def add(a, b): return a+b
... 
>>> add
<function add at 0xb740d22c>
>>> add(3, 4)
7

As you can see there's no real difference between the two "add".

It's different though with bound methods (obtained from an instance rather than a class):

>>> add = X().add
>>> add
<bound method X.add of <__main__.X object at 0xb740e0ec>>

The documentation is also clear that ismethod() "Return true if the object is a bound method written in Python.".  Maybe an additional note can be added to state that "unbound methods" are not included, and that are instead recognized by isfunction().

In my opinion, the Python 2.7 results are wrong.

In Python 2.7, inspect.ismethod returns True for both bound and unbound methods -- ie., is broken according to the documentation.  As a workaround, I'm using:

def is_bound_method(obj):
    return hasattr(obj, '__self__') and obj.__self__ is not None

is_bound_method also works for methods of classes implemented in C, e.g., int:

>>> a = 1
>>> is_bound_method(a.__add__)
True
>>> is_bound_method(int.__add__)
False

But is not very useful in that case because inspect.getargspec does not work for functions implemented in C.

is_bound_method works unchanged in Python 3, but as noted above, in Python 3, inspect.ismethod properly distinguishes between bound and unbound methods, so it is not necessary.

I agree that the docs for inspect.ismethod() for Python 2 are wrong.

The docs say: "Return true if the object is a bound method written in Python."

However, it also returns True for an unbound method:

>>> class A:
...     def meth(self):
...         pass
... 
>>> A.meth
<unbound method A.meth>
>>> import inspect
>>> inspect.ismethod(A.meth)
True

I checked the tests on 2.7 and found this:

        # contrary to spec, ismethod() is also True for unbound methods
        # (see #1785)
        self.assertIn(('f', B.f), inspect.getmembers(B, inspect.ismethod))

#1785 also has some discussion about this.

This patch fixes Python 2.7.

New changeset 813a0e0934ce by Victor Stinner in branch '2.7':
Fix inspect.ismethod() doc
https://hg.python.org/cpython/rev/813a0e0934ce

Thanks Anna, I pushed your doc fix.

Can you please sign the Python Contributor Agreement?
https://www.python.org/psf/contrib/

New changeset a90b39aa6af4 by Victor Stinner in branch '2.7':
Issue #16851: Add Anna Koroliuk to Misc/ACKS
https://hg.python.org/cpython/rev/a90b39aa6af4

Sounds like this can be closed?