docs/sys: print_exception: Fixes/clarifications.

docs/library/sys.rst

@@ -25,7 +25,7 @@ Functions
       ``traceback`` module in CPython. Unlike ``traceback.print_exception()``,
       this function takes just exception value instead of exception type,
       exception value, and traceback object; `file` argument should be
-      positional; further arguments are not support. Compliant
+      positional; further arguments are not supported. CPython-compatible
       ``traceback`` module can be found in micropython-lib.
 
 Constants