Section 2. The Commonwealth of Pennsylvania, by the Department of Property and Supplies, with the approval of the Governor, and any agency of the Commonwealth or instrumentality of government, including the General State Authority, shall have the power and authority to enter into contracts with any housing authority, either before said housing authority undertakes a project whereby it shall demolish, clear or remove buildings from a slum area, or after it has undertaken and completed such slum clearance project, to lease from such housing authority as lessee for a term not to exceed ninety-nine years, or to acquire from it as purchaser, either the fee, or such right, title, interest or easement as it may deem necessary, in and to the slum area or area included in said project, or any part thereof, when or as cleared, together with any improvements, buildings or structures therein or thereon, owned or about to be acquired by such housing authority, needed by or convenient to the Commonwealth, or any agency thereof, or instrumentality of government, including the General State Authority, for any public purpose or purposes, including the creation of public parks and the erection on the lands contracted for of buildings, improvements and structures deemed necessary for the use of the Commonwealth or needed or convenient for the corporate purposes of such agency or instrumentality of government.