code: def rowcount(self) -> torch.Tensor:
      rowcount = self._rowcount
      if rowcount is not None:
          return rowcount
  
      rowptr = self.rowptr()
      rowcount = rowptr[1:] - rowptr[:-1]
      self._rowcount = rowcount
      return rowcount
  
imports: import warnings
  from typing import List, Optional, Tuple
  import torch
  from torch_scatter import scatter_add, segment_csr
  from torch_sparse.utils import Final, index_sort
label_desc: Use image node_id 17 for calling the SparseStorage obj's underlying member method code with example usage: obj.rowcount() and returns: rowcount, rowcount