LDAP - AD password update

def changePassword(userEmail, oldPassword, newPassword):
    try:
        ldap.set_option(ldap.OPT_X_TLS_REQUIRE_CERT, ldap.OPT_X_TLS_NEVER)

        ldap_client = ldap.initialize("ldap://127.0.01.1:389")
        ldap_client.set_option(ldap.OPT_REFERRALS, 0)
        ldap_client.set_option(ldap.OPT_PROTOCOL_VERSION, 3)
        ldap_client.set_option(ldap.OPT_X_TLS,ldap.OPT_X_TLS_DEMAND)
        ldap_client.set_option( ldap.OPT_X_TLS_DEMAND, True )
        ldap_client.set_option( ldap.OPT_DEBUG_LEVEL, 255 )
        ldap_client.simple_bind_s(ADMIN_EMAIL, ADMIN_PASSWORD)

        # Set AD password
        #unicode_pass = unicode('\"' + newPassword + '\"', "iso-8859-1")
        unicode_pass = newPassword
        password_value = unicode_pass.encode("utf-16-le")
        add_pass = [(ldap.MOD_REPLACE, 'unicodePwd', [password_value]),( ldap.MOD_REPLACE, 'unicodePwd', [password_value])]

        # Replace password
        try:
          user_dn = 'CN=%s,DC=mydomain,DC=com' % username
          ldap_client.modify_s(user_dn, add_pass)
          print "Active Directory password for", username, \
                "was set successfully!"
        except ldap.LDAPError, e:
          sys.stderr.write('Error setting AD password for: ' + username + '\n')
          sys.stderr.write('Message: ' + str(e) + '\n')
          ldap_client.unbind_s()
          return 'SOME_PROBLEM'
        ldap_client.unbind_s()
        return 'AUTHENTICATED'
    except ldap.INVALID_CREDENTIALS:
        ldap_client.unbind()
        return 'INVALID_CREDENTIALS'
    except ldap.SERVER_DOWN:
        return 'SERVER_UNAVAILABLE'