All bonds and certificates of indebtedness issued under authority of sections 6117.01 to 6117.45, inclusive, and 6103.02 to 6103.30, inclusive, of the Revised Code, prior to May 10, 1927, which have been sold for not less than par and accrued interest and the proceeds thereof paid into the treasury, are binding obligations of the political subdivision issuing the same, without regard to whether any special assessments anticipated by such bonds were made prior to the issuance thereof.