code: def spmm_mean(src, edge_index, size, flow="target_to_source"):
      out = spmm_add(src, edge_index, size, flow)
      count = spmm_add(
          tf.ones([tf.shape(src)[0], 1]), edge_index, size, flow
      )
      return out / count
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow
label_desc: Use image node_id 2 for calling a global function with example usage: spmm_mean(src, edge_index, size, flow) and returns: unknown