def add_option(self, K=None, price=None, St=None, kind="call", pos="long"):
        """Add an option to the object's `options` container."""
        kinds = {
            "call": Call,
            "Call": Call,
            "c": Call,
            "C": Call,
            "put": Put,
            "Put": Put,
            "p": Put,
            "P": Put,
        }
        St = self.St if St is None else St
        option = kinds[kind](St=St, K=K, price=price, pos=pos)
        self.options.append(option)
Add an option to the object's `options` container.