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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 AddSeat(self, seat):
    '''Convenience method to add a seat.

    Return the object path of the new seat.
    '''
    seat_path = '/org/freedesktop/login1/seat/' + seat
    if seat_path in mockobject.objects:
        raise dbus.exceptions.DBusException('Seat %s already exists' % seat,
                                            name=MOCK_IFACE + '.SeatExists')

    self.AddObject(seat_path,
                   'org.freedesktop.login1.Seat',
                   {
                       'Sessions': dbus.Array([], signature='(so)'),
                       'CanGraphical': False,
                       'CanMultiSession': True,
                       'CanTTY': False,
                       'IdleHint': False,
                       'ActiveSession': ('', dbus.ObjectPath('/')),
                       'Id': seat,
                       'IdleSinceHint': dbus.UInt64(0),
                       'IdleSinceHintMonotonic': dbus.UInt64(0),
                   },
                   [
                       ('ActivateSession', 's', '', ''),
                       ('Terminate', '', '', '')
                   ])

    return seat_path