def _apply_features_filter(self, station_codes):
<EOL>if hasattr(self, "<STR_LIT>") and self.features is not None:<EOL><INDENT>station_codes = set(station_codes)<EOL>station_codes = list(<EOL>station_codes.intersection(set(self.features))<EOL>)<EOL><DEDENT>return station_codes<EOL>
If the features filter is set, this will return the intersection of
those filter items and the given station codes.