To keep your messages secret, you and your friend set up a decryption system. Indeed, your messages are in the form of a characters, and each character represents a letter of the alphabet. Here are two lists with each element corresponding to that of the other list respectively: letters = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l' , 'm', 'n', 'o', 'p', 'q', 'r', 's',' t ',' u ',' v ',' w ',' x ',' y ',' z '] characters = [4, 6, 8, '/', 7, 1, 9, 0, 2, 3, '!', '(', 4, '&', 5, '', '', ' ? ','; ','% ',' * ',' ',' ',' + ' ]

In order to read these messages normally, write a python code that takes as input the message full of characters, and returns the message with normal letters. The end result should look like this:

>>> crypt(02)

'hi'