gh-152060: Address review — simplify error message, drop duplicate test case

Author: tonghuaroot

Lib/_pydatetime.py

@@ -359,7 +359,7 @@ def _parse_isoformat_date(dtstr):
     # It is assumed that this is an ASCII-only string of lengths 7, 8 or 10,
     # see the comment on Modules/_datetimemodule.c:_find_isoformat_datetime_separator
     if len(dtstr) not in (7, 8, 10):
-        raise ValueError(f"Invalid isoformat string: {dtstr!r}")
+        raise ValueError("Invalid isoformat string")
     year = int(dtstr[0:4])
     has_sep = dtstr[4] == '-'
 

Lib/test/datetimetester.py

@@ -3758,7 +3758,6 @@ def test_fromisoformat_fails_datetime(self):
             '2009-04-19T12:30:45-00:90:00', # Time zone field out from range
             '2009-04-19T12:30:45-00:00:90', # Time zone field out from range
             '2020-2020',                    # Ambiguous 9-char date portion
-            '2020-1234',                    # Ambiguous 9-char date portion
         ]
 
         for bad_str in bad_strs: