(1) gives, offers, or promises to give, to any witness, or person about to be called as a witness, any bribe, upon any understanding or agreement that the testimony of such witness shall be thereby influenced; or
(2) attempts by any other means fraudulently to induce any person to give false or withhold true testimony—
shall be fined not more than $1,000 or imprisoned not more than 5 years, or both.