I want to implement spread so I calculate the ask and bid price already

class TestStrategy(Strategy):

    def next(self):
        current_price = self.data.Close[-1]
        current_spread = self.data.Spread[-1]
        current_signal = self.data.Signal[-1]


      # Calculate bid and ask prices using the spread in points
        bid_price = current_price - (current_spread * 0.001 / 2)
        ask_price = current_price + (current_spread * 0.001 / 2)

        if current_signal == 1:
            self.buy()

        if current_signal == -1:
            self.sell()

how can I implement the ask and bid here the only arguments in self.buy and self.sell is

def sell(self, *, size=.9999, limit=None, stop=None, sl=None, tp=None)
def buy(self, *, size=.9999, limit=None, stop=None, sl=None, tp=None)