为什么我得到NameError：没有定义全局名称'spacing'

Question

I'm getting a NameError: global name 'spacing' is not defined for and im not sure why

def main():
    print("Project One\n")
    print("To encrypt message enter: 1")
    print("To decrypt messsge enter: 2\n")
    pick = int(input())
    if pick == 1:
        print("Encrypting!")
        spacing()
    elif pick == 2:
       print("Decrypting!")
    else:
        print("Try again")

if __name__ == '__main__':
    main()


def spacing():
    text = raw_input("Please Enter the message to encrypt: ").upper()
    print(text)
    key = raw_input("Please enter a key to encrypt").upper()
    print(key)
    space_ignore = ""
    j = 0
    for i in range(len(text)):
        if ord(text[i]) == 32:
            space_ignore += " "
        else:
            if j < len(key):
                space_ignore += key[j]
                j += 1
            else:
                j = 0
                space_ignore += key[j]
                j += 1
    print(space_ignore)
    return text, space_ignore

Answer 1

Python defines are evaluated in-order relative to other statements. By the time main() runs, spacing() has not yet been defined since control has not yet reached def spacing(): ... . Move your if __name__ == 'main': block to below the definition of spacing .

Answer 2

Put spacing() definition above main definition and the last thing you need to place is this:

if __name__ == '__main__':
    main()

Answer 3

python is a scripting language,would do “line by line” or easy say:from top to end. make the spacing before main.