def test_return_time(self, freezer):
session = Session()
session.start()
freezer.move_to("2020-06-15 18:56:38")
assert str(session.elapsed_time()) == "0:01:41"
def test_init_started_at(self):
session = Session()
session.start()
assert str(session.started_at) == "2020-06-15 18:54:57"
