Python socket with proxy. Authentication Error (407)

Question

Thank you for reading. I was able to make a request with a socket connected to a proxy. But, return a 407. That is, there is an error in authentication in the proxy.

I put a Headers ['proxy-yauthorization'], but it doesn't work. It is sent with Basic + "User: Pass" based64.

def http_proxy_connect(address, proxy = None, auth = None, headers = {}):

    import socket
    import base64

    def valid_address(addr):
        """ Verify that an IP/port tuple is valid """
        return isinstance(addr, (list, tuple)) and len(addr) == 2 and isinstance(addr[0], str) and isinstance(addr[1], (int, int))

    if not valid_address(address):
        raise ValueError('Invalid target address')

    if proxy == None:
        s = socket.socket()
        s.connect(address)
        return s, 0, {}

    if not valid_address(proxy):
        raise ValueError('Invalid proxy address')

    headers = {
        'host': address[0]
    }

    headers['proxy-authorization'] = 'Basic ' + auth
    headers['Proxy-Authorization'] = 'Basic ' + auth
    headers['Proxy-Authenticate'] = 'Basic'

    s = socket.socket()
    s.connect(proxy)
    fp = s.makefile('wr')

    fp.write('CONNECT %s:%d HTTP/1.0\r\n' % address)
    fp.write('\r\n'.join('%s: %s' % (k, v) for (k, v) in headers.items()) + '\r\n\r\n')
    print('\r\n'.join('%s: %s' % (k, v) for (k, v) in headers.items()) + '\r\n\r\n')
    fp.flush()

    statusline = fp.readline().rstrip('\r\n')

    if statusline.count(' ') < 2:
        fp.close()
        s.close()
        raise IOError('Bad response')
    version, status, statusmsg = statusline.split(' ', 2)
    if not version in ('HTTP/1.0', 'HTTP/1.1'):
        fp.close()
        s.close()
        raise IOError('Unsupported HTTP version')
    try:
        status = int(status)
    except ValueError:
        fp.close()
        s.close()
        raise IOError('Bad response')

    response_headers = {}

    while True:
        tl = ''
        l = fp.readline().rstrip('\r\n')
        if l == '':
            break
        if not ':' in l:
            continue
        k, v = l.split(':', 1)
        response_headers[k.strip().lower()] = v.strip()

    fp.close()
    return (s, status, response_headers)

print(http_proxy_connect(('xxxxx',80), ('xxxxx',50000), 'user:pass in base64!'));

I am currently sending in Headers ['proxy-yauthorization'], "Basic User: Pass" in base64.