def Key(key):
    while len(key) < 1:
        print("Please enter a key")
        key = raw_input("What is the key: ")
    while key.isalpha() == True :
        print("Please enter a number!")
        key = raw_input("What is the key: ")
    key=int(key)
    while (key > 25) or (key < -25):
        print("The key must be in between numbers 26 and -26")
        key = int(raw_input("What is the key: "))
    print key
 
key = raw_input("What is the key: ")
Key(key)

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CmEKMjYKMjU=

a
26
25