title: Why do I get this error when installing Jupyter notebook?
body: <pre><code>  ERROR: Command errored out with exit status 1:
     command: 'c:\users\nithi\appdata\local\programs\python\python39\python.exe' 'c:\users\nithi\appdata\local\programs\python\python39\lib\site-packages\pip\_vendor\pep517\_in_process.py' build_wheel 'C:\Users\nithi\AppData\Local\Temp\tmpba_qtkcq'
         cwd: C:\Users\nithi\AppData\Local\Temp\pip-install-dq1r1ff8\argon2-cffi
    Complete output (25 lines):
    running bdist_wheel
    running build
    running build_py
    creating build
    creating build\lib.win-amd64-3.9
    creating build\lib.win-amd64-3.9\argon2
    copying src\argon2\exceptions.py -&gt; build\lib.win-amd64-3.9\argon2
    copying src\argon2\low_level.py -&gt; build\lib.win-amd64-3.9\argon2
    copying src\argon2\_ffi_build.py -&gt; build\lib.win-amd64-3.9\argon2
    copying src\argon2\_legacy.py -&gt; build\lib.win-amd64-3.9\argon2
    copying src\argon2\_password_hasher.py -&gt; build\lib.win-amd64-3.9\argon2
    copying src\argon2\_utils.py -&gt; build\lib.win-amd64-3.9\argon2
    copying src\argon2\__init__.py -&gt; build\lib.win-amd64-3.9\argon2
    copying src\argon2\__main__.py -&gt; build\lib.win-amd64-3.9\argon2
    running build_clib
    building 'argon2' library
    creating build\temp.win-amd64-3.9
    creating build\temp.win-amd64-3.9\extras
    creating build\temp.win-amd64-3.9\extras\libargon2
    creating build\temp.win-amd64-3.9\extras\libargon2\src
    creating build\temp.win-amd64-3.9\extras\libargon2\src\blake2
    C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Tools\MSVC\14.27.29110\bin\HostX86\x64\cl.exe /c /nologo /Ox /W3 /GL /DNDEBUG /MD -Iextras\libargon2\src\..\include -Iextras\libargon2\src\blake2 -IC:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Tools\MSVC\14.27.29110\include /Tcextras\libargon2\src\argon2.c /Fobuild\temp.win-amd64-3.9\extras\libargon2\src\argon2.obj
    argon2.c
    extras\libargon2\src\argon2.c(18): fatal error C1083: Cannot open include file: 'string.h': No such file or directory
    error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\BuildTools\\VC\\Tools\\MSVC\\14.27.29110\\bin\\HostX86\\x64\\cl.exe' failed with exit code 2
    ----------------------------------------
    ERROR: Failed building wheel for argon2-cffi
  Failed to build argon2-cffi
  ERROR: Could not build wheels for argon2-cffi which use PEP 517 and cannot be installed directly
  </code></pre>
  <p>I keep getting this error when I try to install jupyter notebook.
  pip install notebook, this is the command I used on the command line.
  One website suggested to install visual studio C++, Which I did and still no luck. Any help is appreciated. Thank you</p>