code: def approve_assignment(self, assignment_id):
          
          try:
              return self._is_ok(
                  self.mturk.approve_assignment(AssignmentId=assignment_id)
              )
          except ClientError as ex:
              assignment = self.get_assignment(assignment_id)
              raise MTurkServiceException(
                  "Failed to approve assignment {}, {}: {}".format(
                      assignment_id, str(assignment), str(ex)
                  )
              )
docs: Approving an assignment initiates two payments from the
          Requester's Amazon.com account:
              1. The Worker who submitted the results is paid
                 the reward specified in the HIT.
              2. Amazon Mechanical Turk fees are debited.