### Distutils: ValueError: [u'path']

This is a really stupid error that occurs on Windows 64bit when trying to build extension modules using distutils:

```  File "C:\Python27\lib\distutils\command\build_ext.py", line 340, in run
self.build_extensions()
File "setup.py", line 213, in build_extensions
with_ext = self.check_extension_availability(ext)
File "setup.py", line 239, in check_extension_availability
depends=ext.depends)
File "C:\Python27\lib\distutils\msvc9compiler.py", line 473, in compile
self.initialize()
File "C:\Python27\lib\distutils\msvc9compiler.py", line 383, in initialize
vc_env = query_vcvarsall(VERSION, plat_spec)
File "C:\Python27\lib\distutils\msvc9compiler.py", line 299, in query_vcvarsall
raise ValueError(str(list(result.keys())))
ValueError: [u'path']
```

The workaround is to take the bat-file in `C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\bin\vcvars32.bat` and copy it to `C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\bin\amd64\vcvarsamd64.bat`. Not that easy to figure out!