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Change the status of a decorator function from method to function

[Updated]: answer in the line below the question

I have a validation program, and one goal is for the logic in the decorator to know if the function that it decorates is a class method or a regular function. This is strange. The following is the code in Python 2.6:

def decorate(f):
    print 'decorator thinks function is', f
    return f

class Test(object):
    @decorate
    def test_call(self):
        pass

if __name__ == '__main__':
    Test().test_call()
    print 'main thinks function is', Test().test_call

Then at execution:

decorator thinks function is <function test_call at 0x10041cd70>
main thinks function is <bound method Test.test_call of <__main__.Test object at 0x100425a90>>

Any clue about what is going wrong, and if it is possible that @decorate is correctly inferring that test_call is a method?

[Answer] The answer of carl below is almost perfect. I had a problem using a decorator in a method that calls subclasses. I adapted his code to enable im_func comparison on superclass members:

ismethod = False
for item in inspect.getmro(type(args[0])):
    for x in inspect.getmembers(item):
        if 'im_func' in dir(x[1]):
            ismethod = x[1].im_func == newf
            if ismethod:
                break
    else:
        continue
    break
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import inspect
ismethod = inspect.getargspec(method).args[0] == 'self'

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import inspect

def decorate(f):
    def detect(*args, **kwargs):
        try:
            members = inspect.getmembers(args[0])
            members = (x[1].im_func for x in members if 'im_func' in dir(x[1]))
            ismethod = detect in members
        except:
            ismethod = False
        print ismethod

        return f(*args, **kwargs)
    return detect

@decorate
def foo():
    pass

class bar(object):
    @decorate
    def baz(self):
        pass

foo() # prints False
bar().baz() # prints True
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class Test:
    @decorate( method = True )
    def test_call:
        ...

@decorate( method = False )
def test_call:
    ...
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def decorate(f):
  print 'decorator thinks function is', f
  return f

class Test(object):
  @decorate
  def test_call(self):
    pass
  def test_call_2(self):
    pass

if __name__ == '__main__':
  print 'main thinks function is', Test.test_call
  print 'main thinks function 2 is', Test.test_call_2

:

decorator thinks function is <function test_call at 0x100426b18>
main thinks function is <unbound method Test.test_call>
main thinks function 2 is <unbound method Test.test_call_2>

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