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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 get_appointment_group(self, appointment_group):
 """ Return single Appointment Group by id :calls: `GET /api/v1/appointment_groups/:id \ <https://canvas.instructure.com/doc/api/appointment_groups.html#method.appointment_groups.show>`_ :param appointment_group: The ID of the appointment group. :type appointment_group: :class:`canvasapi.appointment_group.AppointmentGroup` or int :rtype: :class:`canvasapi.appointment_group.AppointmentGroup` """

        from canvasapi.appointment_group import AppointmentGroup

        appointment_group_id = obj_or_id(
            appointment_group, "appointment_group", (AppointmentGroup,)
        )

        response = self.__requester.request(
            'GET',
            'appointment_groups/{}'.format(appointment_group_id)
        )
        return AppointmentGroup(self.__requester, response.json())