code: def refmap_init(data, sample, force):
      
      ## make some persistent file handles for the refmap reads files
      sample.files.unmapped_reads = os.path.join(data.dirs.edits, 
                                    "{}-refmap_derep.fastq".format(sample.name))
      sample.files.mapped_reads = os.path.join(data.dirs.refmapping,
                                    "{}-mapped-sorted.bam".format(sample.name))
docs: create some file handles for refmapping