'Assert that an object has zero length.
Args:
container: Anything that implements the collections.Sized interface.
msg: Optional message to report on failure.'

def assertEmpty(self, container, msg=None):

    if (not isinstance(container, collections.Sized)):
        self.fail('Expected    a    Sized    object,    got:    {!r}'.format(type(container).__name__), msg)
    if len(container):
        self.fail('{!r}    has    length    of    {}.'.format(container, len(container)), msg)
