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.