def main():
    # Create the dictionary for the encryption codes.
    codes = {'A':'!', 'a':'0', 'B':'@', 'b':'9', 'C':'#',
             'c':'8', 'D':'$', 'd':'7', 'E':'%', 'e':'6',
             'F':'^', 'f':'5', 'G':'&', 'g':'4', 'H':'*',
             'h':'3', 'I':';', 'i':'2', 'J':'~', 'j':'1',
             'K':'x', 'k':'?', 'L':'b', 'l':'Y', 'M':'e',
             'm':'q', 'N':'a', 'n':'c', 'O':'f', 'o':'D',
             'P':'j', 'p':'G', 'Q':'B', 'q':'J', 'R':'K',
             'r':'E', 'S':'A', 's':'d', 'T':'I', 't':'L',
             'U':'C', 'u':'>', 'V':'<', 'v':'/', 'W':'F',
             'w':'k', 'X':'r', 'x':'R', 'Y':'t', 'y':'o',
             'Z':'n', 'z':'s', ' ': ' '}

    # Get the encrypted word file.
    encrypted_file = 'encrypted_words.txt'

    # Decrypt the file and print it out.
    print('Below are the decrypted words:')
    print()
    print(decryption(codes, encrypted_file)


# the decryption function accepts the codes and the encrypted
# words, inverts the key-value pair in the codes and decrypts
# the encrypted words.
def decryption(codes, encrypted_file):
    # Create an empty string to stored the decryption.
    decrypted_words = ''

    # Create another dictionary with the key-value pair
    # inverted.
    inverted_codes = {val: key for key, val in codes.items()}

    # Open the encrypted file for reading.
    with open(encrypted_file) as file_object:
        decrypted = file_object.read()

        # Perform the decryption.
        for char in decrypted:
            if char in inverted_codes:
                decrypted_words += inverted_codes[char]