code: def extract_histogram(spatial_ops, normalize=True):
      out = []
      for idx, nf in enumerate(spatial_ops["neighbour_finder"]):
          dist_meters = nf.dist_meters
          temp = {}
          for dist_meter in dist_meters:
              hist = dist_meter.histogram.copy()
              if normalize:
                  hist /= hist.sum()
              temp[str(dist_meter.radius)] = hist.tolist()
              dist_meter.reset()
          out.append(temp)
      return out
  
file_path: torch-points3d/torch_points3d/utils/debugging_vars.py
imports: import numpy
label_desc: Use image node_id 1 for calling a global function with example usage: extract_histogram(spatial_ops, normalize) and returns: out