gh-135468: Improve BaseHandler.http_error_default() parameter descriptions (#136797)

Co-authored-by: Adam Turner <[email protected]>

Author: vgiane

Doc/library/urllib.request.rst

@@ -829,10 +829,13 @@ The following attribute and methods should only be used by classes derived from
    errors.  It will be called automatically by the  :class:`OpenerDirector` getting
    the error, and should not normally be called in other circumstances.
 
-   *req* will be a :class:`Request` object, *fp* will be a file-like object with
-   the HTTP error body, *code* will be the three-digit code of the error, *msg*
-   will be the user-visible explanation of the code and *hdrs* will be a mapping
-   object with the headers of the error.
+   :class:`OpenerDirector` will call this method with five positional arguments:
+
+   1. a :class:`Request` object,
+   #. a file-like object with the HTTP error body,
+   #. the three-digit code of the error, as a string,
+   #. the user-visible explanation of the code, as as string, and
+   #. the headers of the error, as a mapping object.
 
    Return values and exceptions raised should be the same as those of
    :func:`urlopen`.