class_docstr: A classic batch object wrapper with :class:`Pair`. Used for Dense Pair Batch (ie pointcloud with fixed size).
      
class_docstr_tok: ["A","classic","batch","object","wrapper","with",":","class",":","`","Pair","`",".","Used","for","Dense","Pair","Batch","(","ie","pointcloud","with","fixed","size",")","."]
docstr: Returns the number of graphs in the batch.
docstr_tok: ["Returns","the","number","of","graphs","in","the","batch","."]
code: def num_graphs(self):
      """Returns the number of graphs in the batch."""
      return self.batch[-1].item() + 1
  
imports: import torch
  from typing import List, Optional
  from torch_geometric.data import Data
  from torch_geometric.data import Batch
  from torch_points3d.datasets.multiscale_data import MultiScaleBatch, MultiScaleData
  import re
label_desc: Use image node_id 3 for calling the DensePairBatch obj's underlying member method code with example usage: obj.num_graphs() and returns: unknown