def map_files(self, local_files):
        """Build a dictionary mapping local paths to scratch paths.

        Parameters
        ----------

        local_files : list
            List of filenames to be mapped to scratch area

        Returns dict
            Mapping local_file : fullpath of scratch file
        """
        ret_dict = {}
        for local_file in local_files:
            ret_dict[local_file] = self.get_scratch_path(local_file)
        return ret_dict