code: def _delly_exclude_file(items, base_file, chrom):
      
      base_exclude = sshared.prepare_exclude_file(items, base_file, chrom)
      out_file = "%s-delly%s" % utils.splitext_plus(base_exclude)
      with file_transaction(items[0], out_file) as tx_out_file:
          with open(tx_out_file, "w") as out_handle:
              with open(base_exclude) as in_handle:
                  for line in in_handle:
                      parts = line.split("\t")
                      if parts[0] == chrom:
                          out_handle.write(line)
                      else:
                          out_handle.write("%s\n" % parts[0])
      return out_file
docs: Prepare a delly-specific exclude file eliminating chromosomes.
      Delly wants excluded chromosomes listed as just the chromosome, with no coordinates.