title: setup.py install running egg_info error: [Errno 13] Permission denied regarless of install directory
body: <p>I encountered a bug-like feature of setup.py where I am getting the Permission denied error regardless where I want to install the package without root privilege.</p>
  
  <p>I have a toy python package with a few tiny files, and there is no problem of building it.  There is nothing special in the setup.py file.  I will list one or two of them.</p>
  
  <pre><code>setup (
     name='pmsi',
     entry_points={ 'console_scripts': [ 'pmsi = pmsi.pmsi:main', ] },
  )
  
  
  sudo python3 setup.py install 
  </code></pre>
  
  <p>Gave me no problem at all.  I need to install this package to a particular place and have tried --user, --home, --prefix options; all gave me the same error message at the egg_info step.</p>
  
  <pre><code>python3 setup.py install --user
  running install
  running bdist_egg
  running egg_info
  error: [Errno 13] Permission denied
  </code></pre>
  
  <p>It appears that the install process always tries to copy the egg_info to some system place where I don't have permission to write.  I am not an expert on setup.py, there must be some default rule that I can overwrite either on the command line or setup.py.  Or should I always install to system place as root (that seems to be a bad choice, what if you want to test before a system install).  </p>