def _parseAccept(headers):
def sort(value):<EOL><INDENT>return float(value[<NUM_LIT:1>].get('<STR_LIT:q>', <NUM_LIT:1>))<EOL><DEDENT>return OrderedDict(sorted(_splitHeaders(headers), key=sort, reverse=True))<EOL>
Parse and sort an ``Accept`` header.

The header is sorted according to the ``q`` parameter for each header value.

@rtype: `OrderedDict` mapping `bytes` to `dict`
@return: Mapping of media types to header parameters.