Agency means -
(1) An Executive agency as defined in 5 U.S.C. 105, including the U.S. Postal Service and the U.S. Postal Rate Commission;
(2) A military department as defined in 5 U.S.C. 102;
(3) An agency or court in the judicial branch, including a court as defined in 28 U.S.C. 610, the District Court for the Northern Mariana Islands, and the Judicial Panel on Multidistrict Litigation;
(4) An agency of the legislative branch, including the U.S. Senate and the U.S. House of Representatives; and
(5) Any other independent establishment that is an entity of the Federal Government.