Return type does not propagate to derived class

[MikhailArkhipov]

import unittest
unittest.TestCase.assertRaises().

import unittest
class Simple(unittest.TestCase):
 def test_exception(self):
 self.assertRaises(). # nothing

[MikhailArkhipov]

3.x specific. Works in 2.x

[MikhailArkhipov]

Fixed overloads merging, exception is there, but Jedi shows more

[MikhailArkhipov]

The above difference with Jedi is b/c we fetch from Typeshed definitions and they only have exception