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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def calc_resp(password_hash, server_challenge):
 """calc_resp generates the LM response given a 16-byte password hash and the challenge from the Type-2 message. @param password_hash 16-byte password hash @param server_challenge 8-byte challenge from Type-2 message returns 24-byte buffer to contain the LM response upon return """

    # padding with zeros to make the hash 21 bytes long
    password_hash += b'\0' * (21 - len(password_hash))

    res = b''
    dobj = des.DES(password_hash[0:7])
    res = res + dobj.encrypt(server_challenge[0:8])

    dobj = des.DES(password_hash[7:14])
    res = res + dobj.encrypt(server_challenge[0:8])

    dobj = des.DES(password_hash[14:21])
    res = res + dobj.encrypt(server_challenge[0:8])
    return res