What is pip `--no-cache-dir` for?

Question

I recently saw how it is --no-cache-dirused in a Docker file. I have never seen this flag before, and help doesn't explain it:

 --no-cache-dir              Disable the cache.

• Question: What is cached?
• Question: What is the cache used for?
• Question: Why do I want to disable it?

Answer 1

1. Cached : Store in stash or for future use.
2. Is used for
   • save installation files ( .whletc.) of modules that you install via pip
   • keep source files ( .tar.gzetc.) to avoid reloading if not expired
3. :
   • pip install
     • :
       • export PYCURL_SSL_LIBRARY=nss pip install pycurl
       • export PYCURL_SSL_LIBRARY=openssl pip install pycurl --compile --no-cache-dir

https://pip.pypa.io/en/stable/reference/pip_install/#caching  - @emredjan https://pip.pypa.io/en/stable/reference/pip_install/ - @mikea

Answer 2

, --no-cache-dir Docker. Docker, , .

Answer 3

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Answer 4

, DockerFile python, / .