

        method = request.method
        if method is None:
            return not_found()
        if method == &#34;GET&#34;:
            if self.app.oauth_flow is not None:
                oauth_flow: OAuthFlow = self.app.oauth_flow
                bolt_req: BoltRequest = to_bolt_request(request, body)
                query = bolt_req.query
                is_callback = query is not None and (
                    (_first_value(query, &#34;code&#34;) is not None and _first_value(query, &#34;state&#34;) is