配置python出现的问题

安装python库

我们有的时候需要用到numpy等库，则需要用到pip指令
所以我们需要输入:

pip install numpy

如果是macos则会出现以下报错：

zsh: command not found: pip

没有找到pip指令，经过查找，则需要输入pip3
值得一提的是，在macos里面的python实际上是需要输入指令python3进行完成。

然后输入pip3 install numpy结果如下：

错误信息如下：

ERROR: Exception:
Traceback (most recent call last):
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/urllib3/response.py", line 438, in _error_catcher
    yield
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/urllib3/response.py", line 519, in read
    data = self._fp.read(amt) if not fp_closed else b""
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/cachecontrol/filewrapper.py", line 62, in read
    data = self.__fp.read(amt)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/http/client.py", line 459, in read
    n = self.readinto(b)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/http/client.py", line 503, in readinto
    n = self.fp.readinto(b)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/socket.py", line 704, in readinto
    return self._sock.recv_into(b)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/ssl.py", line 1241, in recv_into
    return self.read(nbytes, buffer)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/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 "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/cli/base_command.py", line 173, in _main
    status = self.run(options, args)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/cli/req_command.py", line 203, in wrapper
    return func(self, options, args)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/commands/install.py", line 315, in run
    requirement_set = resolver.resolve(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/resolver.py", line 94, in resolve
    result = self._result = resolver.resolve(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/resolvelib/resolvers.py", line 472, in resolve
    state = resolution.resolve(requirements, max_rounds=max_rounds)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/resolvelib/resolvers.py", line 341, in resolve
    self._add_to_criteria(self.state.criteria, r, parent=None)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/resolvelib/resolvers.py", line 172, in _add_to_criteria
    if not criterion.candidates:
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/resolvelib/structs.py", line 151, in __bool__
    return bool(self._sequence)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/found_candidates.py", line 140, in __bool__
    return any(self)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/found_candidates.py", line 128, in <genexpr>
    return (c for c in iterator if id(c) not in self._incompatible_ids)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/found_candidates.py", line 32, in _iter_built
    candidate = func()
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/factory.py", line 204, in _make_candidate_from_link
    self._link_candidate_cache[link] = LinkCandidate(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 295, in __init__
    super().__init__(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 156, in __init__
    self.dist = self._prepare()
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 227, in _prepare
    dist = self._prepare_distribution()
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 305, in _prepare_distribution
    return self._factory.preparer.prepare_linked_requirement(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/operations/prepare.py", line 508, in prepare_linked_requirement
    return self._prepare_linked_requirement(req, parallel_builds)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/operations/prepare.py", line 550, in _prepare_linked_requirement
    local_file = unpack_url(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/operations/prepare.py", line 239, in unpack_url
    file = get_http_url(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/operations/prepare.py", line 102, in get_http_url
    from_path, content_type = download(link, temp_dir.path)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/network/download.py", line 145, in __call__
    for chunk in chunks:
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/cli/progress_bars.py", line 144, in iter
    for x in it:
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_internal/network/utils.py", line 63, in response_chunks
    for chunk in response.raw.stream(
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/urllib3/response.py", line 576, in stream
    data = self.read(amt=amt, decode_content=decode_content)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/urllib3/response.py", line 541, in read
    raise IncompleteRead(self._fp_bytes_read, self.length_remaining)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/contextlib.py", line 135, in __exit__
    self.gen.throw(type, value, traceback)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/site-packages/pip/_vendor/urllib3/response.py", line 443, 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 21.2.4; however, version 22.3.1 is available.
You should consider upgrading via the '/Library/Developer/CommandLineTools/usr/bin/python3 -m pip install --upgrade pip' command.

原因：网络问题，下载国外的太慢，需要用到镜像网站，可以选择用清华的镜像网站。

解决办法：

pip install [需要安装的库] -i https://pypi.tuna.tsinghua.edu.cn/simple

同样，如果是macos则需要使pip3指令

比如我这里需要安装numpy库，则需要：

pip3 install numpy -i https://pypi.tuna.tsinghua.edu.cn/simple

安装完成。

如果遇到网络问题则重试即可，这里安装两个库都没有问题

配置python出现的问题

安装python库

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