I ran into this bug while working on the AST compiler.
 The new compiler sets the "lineno" and "filename"
attributes of SyntaxErrors in more cases than the old.
 The problem is that the traceback.py module formats
SyntaxError exceptions differently than pythonrun.c
does.  Attached is a small testcase.  Notice that
traceback.py uses str() to generate the exception line
and that it includes the file and lineno in
parenthesis.  This difference confuses doctest.py.

I guess the parse_syntax_error() logic needs to be
reproduced in traceback.py.