code: def classifications(ctx, classifications, results, readlevel, readlevel_path):
      
  
      # basic operation -- just print
      if not readlevel and not results:
          cli_resource_fetcher(ctx, "classifications", classifications)
  
      # fetch the results
      elif not readlevel and results:
          if len(classifications) != 1:
              log.error("Can only request results data on one Classification at a time")
          else:
              classification = ctx.obj["API"].Classifications.get(classifications[0])
              if not classification:
                  log.error(
                      "Could not find classification {} (404 status code)".format(classifications[0])
                  )
                  return
              results = classification.results(json=True)
              pprint(results, ctx.obj["NOPPRINT"])
  
      # fetch the readlevel
      elif readlevel is not None and not results:
          if len(classifications) != 1:
              log.error("Can only request read-level data on one Classification at a time")
          else:
              classification = ctx.obj["API"].Classifications.get(classifications[0])
              if not classification:
                  log.error(
                      "Could not find classification {} (404 status code)".format(classifications[0])
                  )
                  return
              tsv_url = classification._readlevel()["url"]
              log.info("Downloading tsv data from: {}".format(tsv_url))
              download_file_helper(tsv_url, readlevel_path)
  
      # both given -- complain
      else:
          log.error("Can only request one of read-level data or results data at a time")
docs: Retrieve performed metagenomic classifications