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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 all(self):
 """ Return all registered users http://www.keycloak.org/docs-api/3.4/rest-api/index.html#_users_resource """

        return self._client.get(
            url=self._client.get_full_url(
                self.get_path('collection', realm=self._realm_name)
            )
        )