def _recent_stream_for_dir(dir, maxdate=None):
dir = os.path.abspath(dir)
files = FileReader.ListDatFiles(d=dir)
#The returned list is in ascending order, assume the last is most recent
best_stream = None
for fn in files:
temp_stream = FileReader.bcistream(fn)
temp_date = datetime.datetime.fromtimestamp(temp_stream.datestamp)
if not best_stream\
or (maxdate and temp_date<=maxdate)\
or (not maxdate and temp_date > datetime.datetime.fromtimestamp(best_stream.datestamp)):
best_stream = temp_stream
return best_stream
