Documented `set_python_build` function that is undefined?

[jakirkham]

In the docs here (see below) and the legacy CPython docs, set_python_build is covered

distutils/docs/distutils/apiref.rst

Lines 1554 to 1559 in 2e8c2a2

	.. function:: set_python_build()
	Inform the :mod:`distutils.sysconfig` module that it is being used as part of
	the build process for Python. This changes a lot of relative locations for
	files, allowing them to be located in the build area rather than in an installed
	Python.

However am not seeing it defined in the code here. It looks like CPython may have removed this a long time ago ( python/cpython#36488 ). If so, would it make sense to drop it from the docs?