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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 delete_user_policy(self, user_name, policy_name):
 """ Deletes the specified policy document for the specified user. :type user_name: string :param user_name: The name of the user the policy is associated with. :type policy_name: string :param policy_name: The policy document to delete. """

        params = {'UserName' : user_name,
                  'PolicyName' : policy_name}
        return self.get_response('DeleteUserPolicy', params, verb='POST')