Python cipher phrase decryption

You have the following cipher letters with their respective keys

cipher = ['u', 'l', 'v', 'w', 'x', 'k', 'y', 'z', 'a', 'b', 'c', 'f', '!', '9', '8', '7', '6', '5', '4', '3', '2', '1', '0']
keys = ['a', 'g', 'y', 'c', 'm', 'n', 'p', 't', 'u', 'h', 'o', 'r', ' ', '1', '2', '3', '4', '5', '6', '7', '8', '0', '1']

Implement a function decrypt() that takes a cipher phrase or string as an input parameter. This function will decrypt the cipher string and return the decryption.

def decrypt(string):
	return descryptedstring

You should also implement the following helper functions:

• The function getIndex( ) takes as parameter a character at a time from the cipher phrase and returns its index in the cipher list. If the character isn’t found in the cipher list, the function returns -1.

def getIndex(c):
	return index

• The function getChar( ) takes as parameter a character at a time and returns the corresponding character from the keys list or otherwise ‘#’ if the character isn’t found in the keys list.
  

def getChar(c):
	return something

Sample Input and output :

>>> Enter the phrase to decrypt: wxyaz!919
The decryption: cmput 101
>>> Enter the phrase to decrypt: yux!456
The decryption: pam 654
>>> Enter the phrase to decrypt: u!yvzbck!yfclfux
The decryption: a python program
>>> Enter the phrase to decrypt: mnop999
The decryption: ####111

Solution in Python3

cipher = ['u', 'l', 'v', 'w', 'x', 'k', 'y', 'z', 'a', 'b', 'c', 'f', '!', '9', '8', '7', '6', '5', '4', '3', '2', '1', '0']
keys = ['a', 'g', 'y', 'c', 'm', 'n', 'p', 't', 'u', 'h', 'o', 'r', ' ', '1', '2', '3', '4', '5', '6', '7', '8', '0', '1']

def getIndex(c):
    try:
        return cipher.index(c)
    except ValueError:
        return -1
        
def getChar(c):
    index = getIndex(c)
    if index==-1:
        return "#"
    else:
        return keys[index]
        
def decrypt(string):
    decrypted = ""
    for i in string:
        decrypted+=getChar(i)
    return decrypted
    
text = input("Enter the phrase to decrypt: ")
print("The decryption:", decrypt(text))