Backport PR
#4738: don't inject help into user_ns...
Backport PR
#4738: don't inject help into user_ns
because it's in builtins. I presume this was for old Pythons, but it doesn't seem necessary for ≥ 2.7.
Prompted because the injection fails on 3.4, causing the warning:
WARNING: help() not available - check site.py
but help actually works just fine.