def list_compounds(self, periods):
    balance_list = []
    for period in range((periods + 1)):
        balance_list.append(self.calculate_compound(period))
    return balance_list
def list_compounds(self, periods):
    balance_list = []
    for period in range((periods + 1)):
        balance_list.append(self.calculate_compound(period))
    return balance_list