It is a defence to a prosecution for an offence against section 34 and section 35, in relation to an advertisement, if the defendant proves that—
(a) the defendant's business includes publishing or arranging for the publication of advertisements; and
(b) the defendant—
(i) received the advertisement in the ordinary course of the business; and
(ii) did not
know, and had no reason to believe, that publishing it would be an offence
against section 34 or section 35.