The board of directors of the irrigation district shall file in the district court of the county in which their office is situated a petition, praying in effect that the proceedings aforesaid may be examined, approved and confirmed by the court. The petition shall state generally that the irrigation district was duly organized and the first board of directors elected, that due and lawful proceedings were taken to issue bonds in an amount to be stated, and that said assessment, list and apportionment were duly made and a copy of said assessment, list and apportionment shall be attached to said petition, and that such bonds or a certain amount of such bonds have been legally sold or exchanged, as the case may be, but the petition need not state other facts showing such proceedings: provided, that after the organization of the district is complete, a petition may be filed for the confirmation of the proceedings so far, or after the authorization of any issue of bonds such petition may be so filed or after the sale or exchange of any issue or any portion of an issue of bonds such petition may be so filed, and where the procedure is by separate petitions for the confirmation of different portions of said proceedings, subsequent proceedings may be in the name of reopening of the same case, but shall not be considered as authorizing any rehearing of the matter theretofore heard and decided.