complete cgi.parse() signature; thanks to Aaron Bingham from docs@

Doc/library/cgi.rst

@@ -284,10 +284,10 @@ These are useful if you want more control, or if you want to employ some of the
 algorithms implemented in this module in other circumstances.
 
 
-.. function:: parse(fp[, keep_blank_values[, strict_parsing]])
+.. function:: parse(fp[, environ[, keep_blank_values[, strict_parsing]]])
 
    Parse a query in the environment or from a file (the file defaults to
-   ``sys.stdin``).  The *keep_blank_values* and *strict_parsing* parameters are
+   ``sys.stdin`` and environment defaults to ``os.environ``).  The *keep_blank_values* and *strict_parsing* parameters are
    passed to :func:`urlparse.parse_qs` unchanged.