confused about why i get a type error when i call an object's method

[pepper at rumbalski.com]

I'm confused about why i get a type error when i call an object's
method.  Here's the example code:
>>> class Foo:
	def __init__(self):
		self.foo = []
	def foo(self):
		print "in foo!"


>>> f = Foo()
>>> dir(f)
['__doc__', '__init__', '__module__', 'foo']
>>> f.foo()

Traceback (most recent call last):
  File "<pyshell#32>", line 1, in <module>
    f.foo()
TypeError: 'list' object is not callable
>>>