Whoever takes or entices any minor under fourteen years of age if a male, or under sixteen years of age if a female, or any person of unsound mind, out of the keeping of the lawful guardian of such minor or person of unsound mind, without the consent of such guardian, is said to kidnap such minor or person from lawful guardianship.

Explanation.— The words "lawful guardian" in this section includes any person lawfully entrusted with the care or custody of such minor or other person.

Exception.— The section does not extend to the act of any person who in good faith believes himself to be the father of an illegitimate child, or who in good faith believes himself to be entitled to the lawful custody of such child, unless such act is committed for an immoral or unlawful purpose.