def _proxy_requires_url_absolute_form(self, parsed_url: Url) -> bool:
        """
        Indicates if the proxy requires the complete destination URL in the
        request.  Normally this is only needed when not using an HTTP CONNECT
        tunnel.
        """
        if self.proxy is None:
            return False

        return not connection_requires_http_tunnel(
            self.proxy, self.proxy_config, parsed_url.scheme
        )

        Indicates if the proxy requires the complete destination URL in the
        request.  Normally this is only needed when not using an HTTP CONNECT
        tunnel.
        
src/urllib3/poolmanager.py