C:Program Files (x86)Python34Scripts>pip install pyv8
Downloading/unpacking pyv8
  Downloading PyV8-0.5.zip
  Running setup.py (path:C:UsersMEAppDataLocalTemppip_build_Sebastian Weidemannpyv8setup.py) egg_info for package pyv8
    Traceback (most recent call last):
      File "<string>", line 17, in <module>
      File "C:UsersMEAppDataLocalTemppip_build_Sebastian Weidemannpyv8setup.py", line 17, in <module>
        include_dirs += os.environ["INCLUDE"].split(';')
      File "C:Program Files (x86)Python34libos.py", line 651, in __getitem__
        raise KeyError(key) from None
    KeyError: 'INCLUDE'
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):

  File "<string>", line 17, in <module>

  File "C:UsersMEAppDataLocalTemppip_build_Sebastian Weidemannpyv8setup.py", line 17, in <module>

    include_dirs += os.environ["INCLUDE"].split(';')

  File "C:Program Files (x86)Python34libos.py", line 651, in __getitem__

    raise KeyError(key) from None

KeyError: 'INCLUDE'

----------------------------------------
Cleaning up...
Command python setup.py egg_info failed with error code 1 in C:UsersMEAppDataLocalTemppip_build_MEpyv8
Storing debug log for failure in C:UsersMEpippip.log

C:Program Files (x86)Python34Scripts>