We only stock Pepsi. A man and his friend walk up to a bar and wave a hand to get the bartender's attention. ""Good evening. Could we have one bottle of coke, and a bottle of moose piss, please?"" One of them asks. ""Ah, I'm very sorry."" Says the barman apologetically. ""But we only stock pepsi. Is that okay?"" The customers don't look particularly pleased, but they consent. One minute later, the barman returns with their order.... One pepsi, and one coke.