code: def _make_default_global_block_opt(global_block_opt, default_reducer):
      """Default options to be used in the GlobalBlock of a generic GraphNetwork."""
      global_block_opt = (
          dict(global_block_opt.items()) if global_block_opt else {}
      )
      for k, v in _DEFAULT_GLOBAL_BLOCK_OPT.items():
          global_block_opt[k] = global_block_opt.get(k, v)
      for key in ["edges_reducer", "nodes_reducer"]:
          global_block_opt[key] = global_block_opt.get(
              key, default_reducer
          )
      return global_block_opt
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from graph_nets import _base
  from graph_nets import blocks
  import tensorflow
label_desc: Use image node_id 3 for calling a global function with example usage: _make_default_global_block_opt(global_block_opt, default_reducer) and returns: global_block_opt