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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_user(self, user, is_admin=False):
 """ Adds a new user and if the first user makes the user an admin and the owner. """

        users_count = self.users.all().count()
        if users_count == 0:
            is_admin = True
        # TODO get specific org user?
        org_user = self._org_user_model.objects.create(
            user=user, organization=self, is_admin=is_admin
        )
        if users_count == 0:
            # TODO get specific org user?
            self._org_owner_model.objects.create(
                organization=self, organization_user=org_user
            )

        # User added signal
        user_added.send(sender=self, user=user)
        return org_user