Section 20: In the last two preceding sections the expression ~e:ition

"corresponding law" means any law stated in a certificate ~xpre~sion purporting to be issued by or on behalf of the Government of :· colesf,ondany country outside the Colony to be a law providing for the mg aw. control and regulation in that country of the manufacture, sale, use, export and import of drugs in accordance with the provisions of the International Opium Convention signed at the Hague on the twenty-third day of January, nineteen hundred and twelve or of the International Opium Convention signed at Geneva on the nineteenth day of February, nineteen hundred and twenty-five or of the International Convention signed at Geneva on the thirteenth day of July, nineteen hundred and thirty-one, and any statement in any such certificate as to the effect of the law mentioned in the certificate, or any statement in any such certificate that any facts constitute an offence against that law, shall be conclusive.