The purposes of this title include the partition of the Federal National Mortgage Association as heretofore existing into two separate and distinct corporations, each of which shall have continuity and corporate succession as a separated portion of the previously existing corporation. One of such corporations, to be known as Federal National Mortgage Association, will be a Government-sponsored private corporation, will retain the assets and liabilities of the previously existing corporation accounted for under section 1719 of this title, and will continue to operate the secondary market operations authorized by such section 1719. The other, to be known as Government National Mortgage Association, will remain in the Government, will retain the assets and liabilities of the previously existing corporation accounted for under sections 1720 1