Checking for rhinoscript BooleanUnion failure returning an all-zero GUID

I have a python script that calls rs.BooleanUnion. In some cases the union appears to fail but it returns an all-zero GUID 00000000-0000-0000-0000-000000000000 instead of None.
How can I check if the System.Guid object is an all-zero GUID so I can handle the error in my code? The resulting variable type is System.Guid so i can’t do the usual handling like so:

if not boolean_result: dosomething

“System.Guid” overrides the equal and unequal operator:

 if (someGuid != System.Guid("00000000-0000-0000-0000-000000000000") )
      print("someGuid is not empty")

System.Guid.Empty should be the same as writing System.Guid(“00000000-0000-0000-0000-000000000000”)