title: How can I set log level used by distutils when using pip?
body: <p>I'm trying to find out what's the reason of <code>error: Unable to find vcvarsall.bat</code> after <code>pip install greenlet</code>. I'd like to set log level used by distutils so that debug messages like <a href="http://hg.python.org/cpython/file/8527427914a2/Lib/distutils/msvc9compiler.py#l240" rel="noreferrer"><code>log.debug("Unable to find productdir in registry")</code></a> would get printed. After looking at <a href="http://hg.python.org/cpython/file/8527427914a2/Lib/distutils/dist.py#l423" rel="noreferrer"><code>def parse_command_line(self):</code></a> I thought <code>pip install --install-option="-vv" greenlet</code> should work but it doesn't (verbosity is still 1).</p>
  
  <p>How can I do this?</p>