(a) An unmarried man or woman commits the offense of marrying a bigamist when he marries a person whom he knows to be the wife or husband of another.

(b) It shall be an affirmative defense that the prior spouse of the bigamist has been continually absent for a period of seven years, during which time the accused did not know the prior spouse of the bigamist to be alive, or that the accused reasonably believed the bigamist was eligible to remarry.

(c) A person convicted of the offense of marrying a bigamist shall be punished by imprisonment for not less than one nor more than ten years.