This module provides a monotonic() function which returns the value (in
fractional seconds) of a clock which never goes backwards.

On Python 3.3 or newer, monotonic will be an alias of time.monotonic from the
standard library. On older versions, it will fall back to an equivalent
Linux implementation: clock_gettime.

If no suitable implementation exists for the current platform, attempting to
import this module (or to import from it) will cause a RuntimeError exception
to be raised.