下载LXML报错

# 具体遇到的问题
如何升级pip命令
# 报错信息的截图

E:\python课件\入门主流框架Scrapy与爬虫项目\初探网络爬虫\爬虫进阶与实战\第二课python爬虫进阶与实战\第二课   python爬虫进阶与实战>pip install lxml

Collecting lxml

  WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAI

LED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1108)'))': /packages/99/cd/7aecddd5e0290379cf40e47490f3dc04a2e6ea8317c1d21ff2caad24f284/lxml-4.6.1-cp38-c

p38-win_amd64.whl

  WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAI

LED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1108)'))': /packages/99/cd/7aecddd5e0290379cf40e47490f3dc04a2e6ea8317c1d21ff2caad24f284/lxml-4.6.1-cp38-c

p38-win_amd64.whl

  Downloading lxml-4.6.1-cp38-cp38-win_amd64.whl (3.5 MB)

     |█                               | 133 kB 37 kB/s eta 0:01:32ERROR: Exception:

Traceback (most recent call last):

  File "d:\python\lib\site-packages\pip\_vendor\urllib3\response.py", line 425, in _error_catcher

    yield

  File "d:\python\lib\site-packages\pip\_vendor\urllib3\response.py", line 507, in read

    data = self._fp.read(amt) if not fp_closed else b""

  File "d:\python\lib\site-packages\pip\_vendor\cachecontrol\filewrapper.py", line 62, in read

    data = self.__fp.read(amt)

  File "d:\python\lib\http\client.py", line 454, in read

    n = self.readinto(b)

  File "d:\python\lib\http\client.py", line 498, in readinto

    n = self.fp.readinto(b)

  File "d:\python\lib\socket.py", line 669, in readinto

    return self._sock.recv_into(b)

  File "d:\python\lib\ssl.py", line 1241, in recv_into

    return self.read(nbytes, buffer)

  File "d:\python\lib\ssl.py", line 1099, in read

    return self._sslobj.read(len, buffer)

socket.timeout: The read operation timed out

During handling of the above exception, another exception occurred:

Traceback (most recent call last):

  File "d:\python\lib\site-packages\pip\_internal\cli\base_command.py", line 188, in _main

    status = self.run(options, args)

  File "d:\python\lib\site-packages\pip\_internal\cli\req_command.py", line 185, in wrapper

    return func(self, options, args)

  File "d:\python\lib\site-packages\pip\_internal\commands\install.py", line 332, in run

    requirement_set = resolver.resolve(

  File "d:\python\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 179, in resolve

    discovered_reqs.extend(self._resolve_one(requirement_set, req))

  File "d:\python\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 362, in _resolve_one

    abstract_dist = self._get_abstract_dist_for(req_to_install)

  File "d:\python\lib\site-packages\pip\_internal\resolution\legacy\resolver.py", line 314, in _get_abstract_dist_for

    abstract_dist = self.preparer.prepare_linked_requirement(req)

  File "d:\python\lib\site-packages\pip\_internal\operations\prepare.py", line 467, in prepare_linked_requirement

    local_file = unpack_url(

  File "d:\python\lib\site-packages\pip\_internal\operations\prepare.py", line 255, in unpack_url

    file = get_http_url(

  File "d:\python\lib\site-packages\pip\_internal\operations\prepare.py", line 129, in get_http_url

    from_path, content_type = _download_http_url(

  File "d:\python\lib\site-packages\pip\_internal\operations\prepare.py", line 281, in _download_http_url

    for chunk in download.chunks:

  File "d:\python\lib\site-packages\pip\_internal\cli\progress_bars.py", line 166, in iter

    for x in it:

  File "d:\python\lib\site-packages\pip\_internal\network\utils.py", line 15, in response_chunks

    for chunk in response.raw.stream(

  File "d:\python\lib\site-packages\pip\_vendor\urllib3\response.py", line 564, in stream

    data = self.read(amt=amt, decode_content=decode_content)

  File "d:\python\lib\site-packages\pip\_vendor\urllib3\response.py", line 529, in read

    raise IncompleteRead(self._fp_bytes_read, self.length_remaining)

  File "d:\python\lib\contextlib.py", line 131, in __exit__

    self.gen.throw(type, value, traceback)

  File "d:\python\lib\site-packages\pip\_vendor\urllib3\response.py", line 430, in _error_catcher

    raise ReadTimeoutError(self._pool, None, "Read timed out.")

pip._vendor.urllib3.exceptions.ReadTimeoutError: HTTPSConnectionPool(host='files.pythonhosted.org', port=443): Read timed out.

WARNING: You are using pip version 20.1.1; however, version 20.2.4 is available.

You should consider upgrading via the 'd:\python\python.exe -m pip install --upgrade pip' command.

E:\python课件\入门主流框架Scrapy与爬虫项目\初探网络爬虫\爬虫进阶与实战\第二课python爬虫进阶与实战\第二课   python爬虫进阶与实战>

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# 尝试过的解决思路和结果

# 粘贴全部相关代码，切记添加代码注释（请勿截图）

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