docstr: Tests the default value for the `fields` argument.
docstr_tok: ["Tests","the","default","value","for","the","`","fields","`","argument","."]
code: def test_map_field_default_value(self):
      """Tests the default value for the `fields` argument."""
      graph = graphs.GraphsTuple(**self.graph)
      mapped_fields = []
      graph = graph.map(mapped_fields.append)
      self.assertCountEqual(
          mapped_fields, [graphs.EDGES, graphs.GLOBALS, graphs.NODES]
      )
  
file_path: graph_nets/graph_nets/tests/graphs_test.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  from graph_nets import graphs
  import tensorflow
label_desc: Use image node_id 8 for calling the GraphsTest obj's underlying member method code with example usage: obj.test_map_field_default_value() without return types