For the current ADUser instance, determine if
        the user is a member of a specific group (the group DN is used).
        The result may not be accurate if explicit_membership_only was set to
        True when the object factory method (user() or users()) was
        called.

        :param str group_distinguishedname: The group DistinguishedName

        :return: A boolean indicating whether or not the user is a member of the group
        :rtype: bool

def is_member(self, group_distinguishedname):
        """For the current ADUser instance, determine if
        the user is a member of a specific group (the group DN is used).
        The result may not be accurate if explicit_membership_only was set to
        True when the object factory method (user() or users()) was
        called.

        :param str group_distinguishedname: The group DistinguishedName

        :return: A boolean indicating whether or not the user is a member of the group
        :rtype: bool
        """
        #pylint: disable=no-member
        if group_distinguishedname.lower() in [dn.lower() for dn in self.memberof]:
        #pylint: enable=no-member
            return True
        else:
            return False