Python 2 doesn't have a monotonic clock function, but there's a `monotonic` module that backports Python 3's `time.monotonic` function: https://pypi.org/project/monotonic/ We should vendor this module and use it instead of wall-clock time for measuring build times and such.

We require Python 3.5+ to build. Would it be possible to use Python 3 for whatever it is you are trying to measure?