code: def _write_to_next_free(tag, blob):
      
      ind = 0
      pref = '/tmp/peyotl-' + tag + str(ind)
      while os.path.exists(pref):
          ind += 1
          pref = '/tmp/peyotl-' + tag + str(ind)
      write_as_json(blob, pref)
docs: #WARNING not thread safe just a easy of debugging routine!