'Assert that a certain number of warnings with certain messages were
emitted in a certain order.
@param warnings: A list of emitted warnings, as returned by
C{flushWarnings}.
@param which: A list of strings giving warning messages that should
appear in C{warnings}.
@raise self.failureException: If the warning messages given by C{which}
do not match the messages in the warning information in C{warnings},
or if they do not appear in the same order.'

def _assertWarnings(self, warnings, which):

    self.assertEqual([warning['message'] for warning in warnings], which)
