def get_connection(self, url, proxies=None):
        """Returns a urllib3 connection for the given URL. This should not be
        called from user code, and is only exposed for use when subclassing the
        :class:`HTTPAdapter <requests.adapters.HTTPAdapter>`.

        :param url: The URL to connect to.
        :param proxies: (optional) A Requests-style dictionary of proxies used on this request.
        :rtype: urllib3.ConnectionPool
        """
        proxy = select_proxy(url, proxies)

        if proxy:
            proxy = prepend_scheme_if_needed(proxy, 'http')
            proxy_url = parse_url(proxy)
            if not proxy_url.host:
                raise InvalidProxyURL("Please check proxy URL. It is malformed"
                                      " and could be missing the host.")
            proxy_manager = self.proxy_manager_for(proxy)
            conn = proxy_manager.connection_from_url(url)
        else:
            # Only scheme should be lower case
            parsed = urlparse(url)
            url = parsed.geturl()
            conn = self.poolmanager.connection_from_url(url)

        return conn
Returns a urllib3 connection for the given URL. This should not be
        called from user code, and is only exposed for use when subclassing the
        :class:`HTTPAdapter <requests.adapters.HTTPAdapter>`.

        :param url: The URL to connect to.
        :param proxies: (optional) A Requests-style dictionary of proxies used on this request.
        :rtype: urllib3.ConnectionPool
        
product/gradle-plugin/src/main/python/pip/_vendor/requests/adapters.py