docs: def bin_annotation(annotation=None, subsampling_factor=3):
      """Perform binning on genome annotations such as contig information or bin
      positions.
      """
  
      if annotation is None:
          annotation = np.array([])
      n = len(annotation)
      binned_positions = [annotation[i] for i in range(n) if
                          i % subsampling_factor == 0]
      if len(binned_positions) == 0:
          binned_positions.append(0)
      return np.array(binned_positions)