I am trying to use ArcHydro for ArcGIS Pro (3.1.12) and I am getting errors where the code is calling time.clock() which is has been removed (not just deprecated) as a function in python 3.8
From the Python 3.8 doc:
The function time.clock() has been removed, after having been deprecated since Python 3.3: use time.perf_counter() or time.process_time() instead, depending on your requirements, to have well-defined behavior. (Contributed by Matthias Bussonnier in bpo-36895.)
Mark.