async def METHOD_NAME(self):
    """
    Test multiple, subsequent transactions between two parties.
    """
    await self.overlay(ID1).do_payout(self.peer(ID2), 500)
    await self.overlay(ID1).do_payout(self.peer(ID2), 1500)
    assert self.database(ID1).get_total_taken(self.key_bin(ID1)) == 2000
    assert self.database(ID2).get_total_taken(self.key_bin(ID1)) == 2000