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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_member(self, contact_name, contactgroup_name):
 """Add a contact string to a contact member if the contact group do not exist, create it :param contact_name: contact name :type contact_name: str :param contactgroup_name: contact group name :type contactgroup_name: str :return: None """

        contactgroup = self.find_by_name(contactgroup_name)
        if not contactgroup:
            contactgroup = Contactgroup({'contactgroup_name': contactgroup_name,
                                         'alias': contactgroup_name,
                                         'members': contact_name})
            self.add_contactgroup(contactgroup)
        else:
            contactgroup.add_members(contact_name)