pip install selenium 安装不上

这是报错信息：
Exception:
Traceback (most recent call last):
File “c:\python3\lib\site-packages\pip_vendor\requests\packages\urllib3\connectionpool.py”, line 595, in urlopen
chunked=chunked)
File “c:\python3\lib\site-packages\pip_vendor\requests\packages\urllib3\connectionpool.py”, line 352, in _make_request
self._validate_conn(conn)
File “c:\python3\lib\site-packages\pip_vendor\requests\packages\urllib3\connectionpool.py”, line 831, in validate_conn
conn.connect()
File “c:\python3\lib\site-packages\pip_vendor\requests\packages\urllib3\connection.py”, line 289, in connect
ssl_version=resolved_ssl_version)
File "c:\python3\lib\site-packages\pip_vendor\requests\packages\urllib3\util\ssl.py", line 308, in ssl_wrap_socket
return context.wrap_socket(sock, server_hostname=server_hostname)
File “c:\python3\lib\ssl.py”, line 401, in wrap_socket
_context=self, _session=session)
File “c:\python3\lib\ssl.py”, line 808, in init
self.do_handshake()
File “c:\python3\lib\ssl.py”, line 1061, in do_handshake
self._sslobj.do_handshake()
File “c:\python3\lib\ssl.py”, line 683, in do_handshake
self._sslobj.do_handshake()
ssl.SSLError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:748)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File “c:\python3\lib\site-packages\pip_vendor\requests\adapters.py”, line 423, in send
timeout=timeout
File “c:\python3\lib\site-packages\pip_vendor\requests\packages\urllib3\connectionpool.py”, line 621, in urlopen
raise SSLError(e)
pip._vendor.requests.packages.urllib3.exceptions.SSLError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:748)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File “c:\python3\lib\site-packages\pip\basecommand.py”, line 215, in main
status = self.run(options, args)
File “c:\python3\lib\site-packages\pip\commands\install.py”, line 324, in run
requirement_set.prepare_files(finder)
File “c:\python3\lib\site-packages\pip\req\req_set.py”, line 380, in prepare_files
ignore_dependencies=self.ignore_dependencies))
File “c:\python3\lib\site-packages\pip\req\req_set.py”, line 620, in _prepare_file
session=self.session, hashes=hashes)
File “c:\python3\lib\site-packages\pip\download.py”, line 821, in unpack_url
hashes=hashes
File “c:\python3\lib\site-packages\pip\download.py”, line 659, in unpack_http_url
hashes)
File “c:\python3\lib\site-packages\pip\download.py”, line 853, in _download_http_url
stream=True,
File “c:\python3\lib\site-packages\pip_vendor\requests\sessions.py”, line 488, in get
return self.request(‘GET’, url, **kwargs)
File “c:\python3\lib\site-packages\pip\download.py”, line 386, in request
return super(PipSession, self).request(method, url, *args, **kwargs)
File “c:\python3\lib\site-packages\pip_vendor\requests\sessions.py”, line 475, in request
resp = self.send(prep, **send_kwargs)
File “c:\python3\lib\site-packages\pip_vendor\requests\sessions.py”, line 596, in send
r = adapter.send(request, **kwargs)
File “c:\python3\lib\site-packages\pip_vendor\cachecontrol\adapter.py”, line 47, in send
resp = super(CacheControlAdapter, self).send(request, **kw)
File “c:\python3\lib\site-packages\pip_vendor\requests\adapters.py”, line 497, in send
raise SSLError(e, request=request)
pip._vendor.requests.exceptions.SSLError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:748)