def assertLength(collection: Iterable[Any], expectedLength: int):
    assert (len(collection) == expectedLength), 'Observed length was {} but expected length was {}'.format(len(collection), expectedLength)
def assertLength(collection: Iterable[Any], expectedLength: int):
    assert (len(collection) == expectedLength), 'Observed length was {} but expected length was {}'.format(len(collection), expectedLength)