Update main.py

Author: ilevkivskyi

mypy/main.py

@@ -1458,16 +1458,6 @@ def set_strict_flags() -> None:
 
     options.process_incomplete_features(error_callback=parser.error, warning_callback=print)
 
-    def _bad_error_code_flags(msg: str) -> None:
-        raise CompileError([msg])
-
-    # Processing error codes after plugins have loaded since plugins may
-    # register custom error codes that we don't know about until plugins
-    # have loaded.
-    options._on_plugins_loaded = lambda: options.process_error_codes(
-        error_callback=_bad_error_code_flags
-    )
-
     # Compute absolute path for custom typeshed (if present).
     if options.custom_typeshed_dir is not None:
         options.abs_custom_typeshed_dir = os.path.abspath(options.custom_typeshed_dir)