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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 deactivate_mfa_device(self, user_name, serial_number):
 """ Deactivates the specified MFA device and removes it from association with the user. :type user_name: string :param user_name: The username of the user :type serial_number: string :param seriasl_number: The serial number which uniquely identifies the MFA device. """

        params = {'UserName' : user_name,
                  'SerialNumber' : serial_number}
        return self.get_response('DeactivateMFADevice', params)