Upon the filing of the aforesaid petition, the court in which it shall have been filed shall fix a date, not less than three weeks nor more than five weeks thereafter, for the making of an application pursuant to the prayer of said petition, and notice of the filing thereof and of the date fixed for making such application shall be published by the mayor not less than once a week, for three weeks, in three daily newspapers of general circulation, published in said city, to be designated by the court, and in the legal journal in which legal notices are regularly printed. On or before the date so fixed, all parties in interest, including the taxpayers, the owners, or holders of bonds or other securities of said city, or otherwise, may appear in person or by attorney, and file with the said court a verified answer to the aforesaid petition. Upon the date so appointed for the making of such application, or at such time thereafter, as it or he may fix, the said court or one of the judges thereof shall proceed forthwith to take the testimony of the parties so appearing, and to hear argument thereon, as in other cases, at which taking of testimony and hearing of argument, all parties shall be entitled to present evidence, to be heard, and to file briefs, as the said judge or court may direct.
53 P.S. § 16991