问Python While循环，仅接受整数

EN

def get_input():
    not_valid = True
    while not_valid:
        itemNo = input("your choice: ")
        try:
           itemNo = int(itemNo) #Try convert the input to an integer
           return itemNo
        except TypeError: #That fails - start over
            print("Enter only integers!")

def addItem(menu, order):
    # get item no from user
    itemNo = get_input()
    # validate item no
    if itemNo == -1:
        return itemNo
    while itemNo not in range(1, len(menu) + 1):
        itemNo = int(input('Invalid input, try again: '))
        if itemNo == -1:
            return itemNo