Prohibition of obstruction or molestation in execution of work.

No person shall obstruct or molest any person authorized or empowered by or under this Act, or with whom the Municipality or any of the municipal authorities referred to in section 20 has lawfully contracted, in the execution of his duty or anything which he is authorized or empowered or required to do by virtue, or in consequence, of any of the provisions of this Act or the rules or the regulations made thereunder, or in fulfillment of his contract, as the case may be.