Developer supply system, developer supply container mounting method and developer supply unit

A developer supply container comprising:

• a developer accommodating body configured to contain developer, the developer accommodating body being rotatable about a rotational axis thereof, and the developer accommodating body including a gear portion provided about the rotational axis;
• a developer discharging body in fluid communication with the developer accommodating body, the developer discharging body having a discharge opening configured to discharge the developer, with an end of the discharge opening being positioned at a bottommost side of the developer supply container, and with the developer accommodating body being rotatable relative to the developer discharging body,
• a supporting member supporting the developer accommodating body;
• a handle connected to the supporting member so as to be rotatable relative to the supporting member, the handle being provided at a position which is adjacent to an end of the developer supply container in a direction of the rotational axis and which is on a side opposite to the discharge opening with respect to a position of the gear portion;
• and
• an operating portion including a displacing portion provided on the same side as the discharge opening with respect to the position of the gear portion in the direction of the rotational axis, the displacing portion including displacing portions provided at each of opposite sides of the developer discharging body, each of the displacing portions being positioned below a horizontal plane that includes the rotational axis, the operating portion including a first arm portion connected to one of the displacing portions and a second arm portion connected another of the displacing portions, and the first arm portion and second arm portion being rotatably connected to the handle,
• wherein the displacing portion displaces upwardly in interrelation with the rotation of the handle in a first direction, and the displacing portion displaces downwardly in interrelation with the rotation of the handle in a second direction that is opposite to the first direction.