Move every letter in the provided string forward 10 letters through the alphabet.
If it goes past 'z', start again at 'a'.
Input will be a string with length > 0.
def move_ten(st):
    a = 'abcdefghijklmnopqrstuvwxyzabcdefghij'
    return (''.join([a[a.find(i)+10] for i in st]))
def move_ten(st):
    a = 'abcdefghijklmnopqrstuvwxyzabcdefghij'
    return (''.join([a[a.find(i)+10] for i in st]))