How to use the requests3.core._http.util.url.parse_url function in requests3

def __init__(
        self,
        proxy_url,
        num_pools=10,
        headers=None,
        proxy_headers=None,
        **connection_pool_kw
    ):
        if isinstance(proxy_url, HTTPConnectionPool):
            proxy_url = '%s://%s:%i' % (
                proxy_url.scheme, proxy_url.host, proxy_url.port
            )
        proxy = parse_url(proxy_url)
        if not proxy.port:
            port = DEFAULT_PORTS.get(proxy.scheme, 80)
            proxy = proxy._replace(port=port)
        if proxy.scheme not in ("http", "https"):
            raise ProxySchemeUnknown(proxy.scheme)

        self.proxy = proxy
        self.proxy_headers = proxy_headers or {}
        connection_pool_kw['_proxy'] = self.proxy
        connection_pool_kw['_proxy_headers'] = self.proxy_headers
        super(ProxyManager, self).__init__(
            num_pools, headers, **connection_pool_kw
        )

async def urlopen(self, method, url, redirect=True, **kw):
        """
        Same as :meth:`urllib3.connectionpool.HTTPConnectionPool.urlopen`
        with redirect logic and only sends the request-uri portion of the
        ``url``.

        The given ``url`` parameter must be absolute, such that an appropriate
        :class:`urllib3.connectionpool.ConnectionPool` can be chosen for it.
        """
        u = parse_url(url)
        conn = self.connection_from_host(u.host, port=u.port, scheme=u.scheme)
        # Rewind body position, if needed. Record current position
        # for future rewinds in the event of a redirect/retry.
        body = kw.get('body')
        body_pos = kw.get('body_pos')
        kw['body_pos'] = set_file_position(body, body_pos)
        if 'headers' not in kw:
            kw['headers'] = self.headers
        if self.proxy is not None and u.scheme == "http":
            response = await conn.urlopen(method, url, **kw)
        else:
            response = await conn.urlopen(method, u.request_uri, **kw)
        redirect_location = redirect and response.get_redirect_location()
        if not redirect_location:
            return response

def urlopen(self, method, url, redirect=True, **kw):
        "Same as HTTP(S)ConnectionPool.urlopen, ``url`` must be absolute."
        u = parse_url(url)
        if u.scheme == "http":
            # For proxied HTTPS requests, httplib sets the necessary headers
            # on the CONNECT to the proxy. For HTTP, we'll definitely
            # need to set 'Host' at the very least.
            headers = kw.get('headers', self.headers)
            kw['headers'] = self._set_proxy_headers(url, headers)
        return super(ProxyManager, self).urlopen(
            method, url, redirect=redirect, **kw
        )

def urlopen(self, method, url, redirect=True, **kw):
        """
        Same as :meth:`urllib3.connectionpool.HTTPConnectionPool.urlopen`
        with redirect logic and only sends the request-uri portion of the
        ``url``.

        The given ``url`` parameter must be absolute, such that an appropriate
        :class:`urllib3.connectionpool.ConnectionPool` can be chosen for it.
        """
        u = parse_url(url)
        conn = self.connection_from_host(u.host, port=u.port, scheme=u.scheme)
        # Rewind body position, if needed. Record current position
        # for future rewinds in the event of a redirect/retry.
        body = kw.get('body')
        body_pos = kw.get('body_pos')
        kw['body_pos'] = set_file_position(body, body_pos)
        if 'headers' not in kw:
            kw['headers'] = self.headers
        if self.proxy is not None and u.scheme == "http":
            response = conn.urlopen(method, url, **kw)
        else:
            response = conn.urlopen(method, u.request_uri, **kw)
        redirect_location = redirect and response.get_redirect_location()
        if not redirect_location:
            return response

def __init__(
        self,
        proxy_url,
        num_pools=10,
        headers=None,
        proxy_headers=None,
        **connection_pool_kw
    ):
        if isinstance(proxy_url, HTTPConnectionPool):
            proxy_url = '%s://%s:%i' % (
                proxy_url.scheme, proxy_url.host, proxy_url.port
            )
        proxy = parse_url(proxy_url)
        if not proxy.port:
            port = DEFAULT_PORTS.get(proxy.scheme, 80)
            proxy = proxy._replace(port=port)
        if proxy.scheme not in ("http", "https"):
            raise ProxySchemeUnknown(proxy.scheme)

        self.proxy = proxy
        self.proxy_headers = proxy_headers or {}
        connection_pool_kw['_proxy'] = self.proxy
        connection_pool_kw['_proxy_headers'] = self.proxy_headers
        super(ProxyManager, self).__init__(
            num_pools, headers, **connection_pool_kw
        )

def connection_from_url(self, url, pool_kwargs=None):
        """
        Similar to :func:`urllib3.connectionpool.connection_from_url`.

        If ``pool_kwargs`` is not provided and a new pool needs to be
        constructed, ``self.connection_pool_kw`` is used to initialize
        the :class:`urllib3.connectionpool.ConnectionPool`. If ``pool_kwargs``
        is provided, it is used instead. Note that if a new pool does not
        need to be created for the request, the provided ``pool_kwargs`` are
        not used.
        """
        u = parse_url(url)
        return self.connection_from_host(
            u.host, port=u.port, scheme=u.scheme, pool_kwargs=pool_kwargs
        )

def _set_proxy_headers(self, url, headers=None):
        """
        Sets headers needed by proxies: specifically, the Accept and Host
        headers. Only sets headers not provided by the user.
        """
        headers_ = {'Accept': '*/*'}
        netloc = parse_url(url).netloc
        if netloc:
            headers_['Host'] = netloc
        if headers:
            headers_.update(headers)
        return headers_

def _set_proxy_headers(self, url, headers=None):
        """
        Sets headers needed by proxies: specifically, the Accept and Host
        headers. Only sets headers not provided by the user.
        """
        headers_ = {'Accept': '*/*'}
        netloc = parse_url(url).netloc
        if netloc:
            headers_['Host'] = netloc
        if headers:
            headers_.update(headers)
        return headers_

def __init__(
        self,
        proxy_url,
        username=None,
        password=None,
        num_pools=10,
        headers=None,
        **connection_pool_kw
    ):
        parsed = parse_url(proxy_url)
        if parsed.scheme == 'socks5':
            socks_version = socks.PROXY_TYPE_SOCKS5
            rdns = False
        elif parsed.scheme == 'socks5h':
            socks_version = socks.PROXY_TYPE_SOCKS5
            rdns = True
        elif parsed.scheme == 'socks4':
            socks_version = socks.PROXY_TYPE_SOCKS4
            rdns = False
        elif parsed.scheme == 'socks4a':
            socks_version = socks.PROXY_TYPE_SOCKS4
            rdns = True
        else:
            raise ValueError(
                "Unable to determine SOCKS version from %s" % proxy_url
            )