Problem building LLVM build for VS2010 on CMake

Constructing LLVMBuild project information

CMake Error at CMakeLists.txt:299 (message):

Unexpected failure executing llvm-build: Traceback (most recent call last):

File "C:/OpenSource/llvm/utils/llvm-build/llvm-build", line 3, in <module>

import llvmbuild

File "C:\OpenSource\llvm\utils\llvm-build\llvmbuild\__init__.py", line
1, in <module>

from main import main

ImportError: No module named 'main'

Configuring incomplete, errors occurred!

This is a python problem, you need python 2.7, not 3.x.