为什么这行不通？

Traceback（最近一次调用是最后一次）：File"/用户/ianyi/PycharmProjects/code作业/calculator.py"，第23行，在calnum1=iof（input（"把第一个数字放在这里：\n"））File"/用户/ianyi/PycharmProjects/代码作业/calculator.py"，第4行，在iof if y！=True： number=int（number）ValueError：int（）的无效文字以10为底：'123.123'

def iof(number):
    y = isinstance(number, float)
    if y != True: number = int(number)
    else: number = float(number)
    return number


def calculation(x:int, y:int, operator:str):
    if operator in ["+"]: sum = iof(x + y)
    elif operator in ["-"]: sum = iof(x - y)
    elif operator in ["*"]: sum = iof(x * y)
    elif operator in ["/"]: sum = iof(x / y)
    elif operator in ["%"]: sum = iof(100 * x / y)
    elif operator in ["^"]: sum = iof(x ** y)
    elif operator in ["√"]: sum = x ** 0.5
    return sum

mathmatical, calnum2 = [None, "+", "-", "*", "/", "%", "^", "√"], None
print("\nHello. This is a Calculator.")
for i in range(1):
    if calnum2 == None:
        calnum1 = iof(input("Put the first number here: \n"))
    choice = str(input(f'''Which mathmatical symbol?
    (+ = 1, - = 2, * = 3, / = 4)
    (% = 5, ^ = 6, √ = 7)\n'''))
    if choice == "x": choice = "*"
    if choice.isnumeric(): choice = mathmatical[int(choice)]
    if choice == "%": calnum2 = iof(input(f"{calnum1}% of? "))
    elif choice == "^": calnum2 = iof(input(f"{calnum1} raised to the power of: "))
    elif choice == "√": pass
    elif choice not in ["√", "%"]: calnum2 = iof(input(f"{calnum1} {choice} "))
    else: raise ValueError("um put the right numbers next time")
    sum = calculation(calnum1, calnum2, choice)
    print(sum)