The separate Idle version was eliminated years ago;
idlelib.idlever is no longer used by Idle
and will be removed in 3.6 or later. Use
IDLE_VERSION = version[:version.index(' ')]
# Kept for now only for possible existing extension use
w.warn(__doc__, DeprecationWarning, stacklevel=2)
IDLE_VERSION = version[:version.index(' ')]