How to use the urllib3.ProxyManager function in urllib3

def connect():
    if args.proxy:
        proto, _ = args.proxy.split("://")
        if proto == "http":
            default_headers = urllib3.make_headers(
                proxy_basic_auth='%s:%s' % (args.username, args.password),
            )
            http_proxy = urllib3.ProxyManager(
                args.proxy,
                headers=default_headers
            )
            http = http_proxy.connection_from_url(args.uri["uri"])
        elif proto in ["socks4", "socks5"]:
            http = SOCKSProxyManager(args.proxy)
        else:
            logging.error("Invalid proxy protocol. It must start with 'http://' or "
                  "'socks[45]://'.")
            exit(1)
    else:
        http = urllib3.connection_from_url(args.uri["uri"])
    return http

# cert_file
        cert_file = Configuration().cert_file

        # key file
        key_file = Configuration().key_file

        # ssl_context
        ssl_context = Configuration().ssl_context

        # proxy
        proxy = Configuration().proxy

        # https pool manager
        if proxy:
            self.pool_manager = urllib3.ProxyManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=cert_file,
                key_file=key_file,
                ssl_context=ssl_context,
                proxy_url=proxy
            )
        else:
            self.pool_manager = urllib3.PoolManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=cert_file,

# if not set certificate file, use Mozilla's root certificates.
            ca_certs = certifi.where()

        addition_pool_args = {}
        if configuration.assert_hostname is not None:
            addition_pool_args['assert_hostname'] = configuration.assert_hostname  # noqa: E501

        if maxsize is None:
            if configuration.connection_pool_maxsize is not None:
                maxsize = configuration.connection_pool_maxsize
            else:
                maxsize = 4

        # https pool manager
        if configuration.proxy:
            self.pool_manager = urllib3.ProxyManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,
                key_file=configuration.key_file,
                proxy_url=configuration.proxy,
                **addition_pool_args
            )
        else:
            self.pool_manager = urllib3.PoolManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,

def get_PoolManager():
    """Creates a pool manager with proxy support, if applicable.

    Returns
    -------
    ProxyManager or PoolManager
        ProxyManager if https_proxy is defined, PoolManager otherwise.
    """

    if myproxy:
        return urllib3.ProxyManager(myproxy, num_pools=1, headers=myheaders)

    return urllib3.PoolManager(num_pools=1, headers=myheaders)

tmp_file = os.path.join(self.nvd_db_dir, 'temp_' + cve_year + '.zip')

        # Download zip file (include cve list) and uncompress zip file.
        target_json_name = ''
        self.utility.write_log(20, 'Accessing : {}'.format(target_url))
        self.utility.print_message(OK, 'Get {} CVE list from {}'.format(cve_year, target_url))

        http = None
        ctx = ssl.create_default_context()
        ctx.set_ciphers('DEFAULT')
        # ctx.set_ciphers('DEFAULT@SECLEVEL=1')
        if self.utility.proxy != '':
            self.utility.print_message(WARNING, 'Set proxy server: {}'.format(self.utility.proxy))
            if self.utility.proxy_user != '':
                headers = urllib3.make_headers(proxy_basic_auth=self.utility.proxy_user + ':' + self.utility.proxy_pass)
                http = urllib3.ProxyManager(timeout=self.con_timeout,
                                            headers=self.http_req_header,
                                            proxy_url=self.utility.proxy,
                                            proxy_headers=headers)
            else:
                http = urllib3.ProxyManager(timeout=self.con_timeout,
                                            headers=self.http_req_header,
                                            proxy_url=self.utility.proxy)
        else:
            http = urllib3.PoolManager(timeout=self.con_timeout,
                                       headers=self.http_req_header,
                                       ssl_version=ssl.PROTOCOL_TLS,
                                       ssl_context=ctx)

        try:
            with http.request('GET', target_url, preload_content=False) as res, open(tmp_file, 'wb') as fout:
                shutil.copyfileobj(res, fout)

# if not set certificate file, use Mozilla's root certificates.
            ca_certs = certifi.where()

        addition_pool_args = {}
        if configuration.assert_hostname is not None:
            addition_pool_args['assert_hostname'] = configuration.assert_hostname  # noqa: E501

        if maxsize is None:
            if configuration.connection_pool_maxsize is not None:
                maxsize = configuration.connection_pool_maxsize
            else:
                maxsize = 4

        # https pool manager
        if configuration.proxy:
            self.pool_manager = urllib3.ProxyManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,
                key_file=configuration.key_file,
                proxy_url=configuration.proxy,
                **addition_pool_args
            )
        else:
            self.pool_manager = urllib3.PoolManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,

# if not set certificate file, use Mozilla's root certificates.
            ca_certs = certifi.where()

        addition_pool_args = {}
        if configuration.assert_hostname is not None:
            addition_pool_args['assert_hostname'] = configuration.assert_hostname  # noqa: E501

        if maxsize is None:
            if configuration.connection_pool_maxsize is not None:
                maxsize = configuration.connection_pool_maxsize
            else:
                maxsize = 4

        # https pool manager
        if configuration.proxy:
            self.pool_manager = urllib3.ProxyManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,
                key_file=configuration.key_file,
                proxy_url=configuration.proxy,
                **addition_pool_args
            )
        else:
            self.pool_manager = urllib3.PoolManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,

# if not set certificate file, use Mozilla's root certificates.
            ca_certs = certifi.where()

        addition_pool_args = {}
        if configuration.assert_hostname is not None:
            addition_pool_args['assert_hostname'] = configuration.assert_hostname  # noqa: E501

        if maxsize is None:
            if configuration.connection_pool_maxsize is not None:
                maxsize = configuration.connection_pool_maxsize
            else:
                maxsize = 4

        # https pool manager
        if configuration.proxy:
            self.pool_manager = urllib3.ProxyManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,
                key_file=configuration.key_file,
                proxy_url=configuration.proxy,
                **addition_pool_args
            )
        else:
            self.pool_manager = urllib3.PoolManager(
                num_pools=pools_size,
                maxsize=maxsize,
                cert_reqs=cert_reqs,
                ca_certs=ca_certs,
                cert_file=configuration.cert_file,

self.utility.print_message(OK, 'Get {} CVE list from {}'.format(cve_year, target_url))

        http = None
        ctx = ssl.create_default_context()
        ctx.set_ciphers('DEFAULT')
        # ctx.set_ciphers('DEFAULT@SECLEVEL=1')
        if self.utility.proxy != '':
            self.utility.print_message(WARNING, 'Set proxy server: {}'.format(self.utility.proxy))
            if self.utility.proxy_user != '':
                headers = urllib3.make_headers(proxy_basic_auth=self.utility.proxy_user + ':' + self.utility.proxy_pass)
                http = urllib3.ProxyManager(timeout=self.con_timeout,
                                            headers=self.http_req_header,
                                            proxy_url=self.utility.proxy,
                                            proxy_headers=headers)
            else:
                http = urllib3.ProxyManager(timeout=self.con_timeout,
                                            headers=self.http_req_header,
                                            proxy_url=self.utility.proxy)
        else:
            http = urllib3.PoolManager(timeout=self.con_timeout,
                                       headers=self.http_req_header,
                                       ssl_version=ssl.PROTOCOL_TLS,
                                       ssl_context=ctx)

        try:
            with http.request('GET', target_url, preload_content=False) as res, open(tmp_file, 'wb') as fout:
                shutil.copyfileobj(res, fout)
        except Exception as e:
            self.utility.print_exception(e, 'Access is failure : {}'.format(target_url))
            self.utility.write_log(30, 'Accessing is failure : {}'.format(target_url))

        with zipfile.ZipFile(tmp_file, 'r') as downloaded_zip:

if req['proxy_type'] == 'socks5':
                    if req['verify']:
                        pool = SOCKSProxyManager(
                            proxy_url,
                            cert_reqs='CERT_REQUIRED',
                            ca_certs=certifi.where(),
                        )
                    else:
                        pool = SOCKSProxyManager(proxy_url)
                elif req['proxy_type'] == 'http':
                    if req['proxy_auth']:
                        proxy_headers = make_headers(proxy_basic_auth=req['proxy_auth'])
                    else:
                        proxy_headers = None
                    if req['verify']:
                        pool = ProxyManager(
                            proxy_url,
                            proxy_headers=proxy_headers,
                            cert_reqs='CERT_REQUIRED',
                            ca_certs=certifi.where(),
                        )
                    else:
                        pool = ProxyManager(
                            proxy_url,
                            proxy_headers=proxy_headers,
                        )
                else:
                    raise error.IowebConfigError(
                        'Invalid value of request option `proxy_type`: %s'
                        % req['proxy_type']
                    )
                if use_cache: