I tried to build MongoDB with master branch latest revision on Windows. It failed to build due to ImportError: No module named typing. This issue can be repro from revision c776e095 (https://github.com/mongodb/mongo/commit/c776e095ac25d0426624f4a84c03f0094c3c661f).

Python module typing is supported from python 3.5. But SCons does not run under Python version 3.5. Python 3 and above are not yet supported. Could you please take a look at this? Thanks!

You can repro this issue as the steps below:
1. git clone -c core.autocrlf=true https://github.com/mongodb/mongo D:\MongoDB\src
2. Open a VS 2015 x64 command prompt and browse to D:\MongoDB\src
3. scons all -j4

Error info:
C:\tools\Python2\python.exe buildscripts/idl/idlc.py --base_dir build/opt --header build\opt\mongo\idl\unittest_gen.h --output build\opt\mongo\idl\unittest_gen.cpp src\mongo\idl\unittest.idl
Traceback (most recent call last):
File "buildscripts/idl/idlc.py", line 23, in <module>
import idl.compiler
File "D:\MongoDB\src\buildscripts\idl\idl\compiler.py", line 26, in <module>
from typing import Any, List
ImportError: No module named typing
scons: *** [build\opt\mongo\idl\unittest_gen.cpp] Error 1