code: def add_member(self, user):
          
          user = Transform.to_user(user)
          data = {
              'id': user
          }
          extra = {
              'resource': self.__class__.__name__,
              'query': {
                  'id': self.id,
                  'data': data,
              }
          }
          logger.info('Adding team member using id', extra=extra)
          response = self._api.post(
              url=self._URL['members_query'].format(id=self.id), data=data)
          member_data = response.json()
          return TeamMember(api=self._api, **member_data)
docs: Add member to team
          :param user: User object or user's username
          :return: Added user.