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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_unknown_members(self, members):
 """Add a new member to the unknown members list :param member: member name :type member: str :return: None """

        if not isinstance(members, list):
            members = [members]

        if not hasattr(self, 'unknown_members'):
            self.unknown_members = members
        else:
            self.unknown_members.extend(members)