No suit or action of any kind shall be maintained in any court to set aside or in any way contest or enjoin the levy or collection of any tax or special assessment levied under the provisions of this act after the expiration of thirty days from the time of the levy of such tax or assessment: Provided, That in cases where assessments are levied before the completion and acceptance of any improvement, said thirty days shall not commence to run until the improvement is completed and accepted.
K.S.A. 13-1333