(self)
Add missing fields to return_fields. Additional fields are not
        removed.
Add missing fields to return_fields. Additional fields are not
        removed.
Add missing fields to return_fields . Additional fields are not removed .
def build_return_fields(self):
        """Add missing fields to return_fields. Additional fields are not
        removed."""
        if 'timestamp' not in self.return_fields:
            self.return_fields.append('timestamp')
        for event in self.event_seq:
            self.return_fields.extend(event)
        self.return_fields = list(set(self.return_fields))
def build_return_fields ( self ) : if 'timestamp' not in self . return_fields : self . return_fields . append ( 'timestamp' ) for event in self . event_seq : self . return_fields . extend ( event ) self . return_fields = list ( set ( self . return_fields ) )