All the signature papers shall be filed in the office of the city clerk as one instrument. Within five days after the filing of the petition the city clerk shall ascertain by examination the number of electors whose signatures are appended thereto, and whether this number is at least ten percent of the total number of electors who cast their votes at the last preceding regular municipal election. If he/she finds the petition insufficient or irregular, he/she shall at once notify one or more of the committee or sponsors of that fact, certifying the reasons for his/her finding. The Committee shall then be given thirty days in which to file additional signature papers and to correct the petition in all other particulars. If at the end of that period the petition is found to be still insufficient or irregular the clerk shall file the same in his/her office and shall notify each member of the committee of that fact. The final finding of the insufficiency or irregularity of a petition shall not prejudice the filing of a new petition for the same purpose, nor shall it prevent the council from referring the measure to the electors at the next regular or any special election, at its option.