bpo-44544: add textwrap placeholder arg (GH-27671)

Author: akulakov

Doc/library/textwrap.rst

@@ -21,7 +21,8 @@ functions should be good enough; otherwise, you should use an instance of
                    subsequent_indent="", expand_tabs=True, \
                    replace_whitespace=True, fix_sentence_endings=False, \
                    break_long_words=True, drop_whitespace=True, \
-                   break_on_hyphens=True, tabsize=8, max_lines=None)
+                   break_on_hyphens=True, tabsize=8, max_lines=None, \
+                   placeholder=' [...]')
 
    Wraps the single paragraph in *text* (a string) so every line is at most
    *width* characters long.  Returns a list of output lines, without final
@@ -39,7 +40,7 @@ functions should be good enough; otherwise, you should use an instance of
                    replace_whitespace=True, fix_sentence_endings=False, \
                    break_long_words=True, drop_whitespace=True, \
                    break_on_hyphens=True, tabsize=8, \
-                   max_lines=None)
+                   max_lines=None, placeholder=' [...]')
 
    Wraps the single paragraph in *text*, and returns a single string containing the
    wrapped paragraph.  :func:`fill` is shorthand for  ::