code: def render(self, filepath, *args, **kwargs):
      self.events.append(filepath)
      self.events.append("render")
  
file_path: neupy/tests/layers/graph/test_visualizations.py
imports: import mock
  import tempfile
  import graphviz
  from neupy import layers
  from base import BaseTestCase
label_desc: Use image node_id 3 for calling the MockedDigraph obj's underlying member method code with example usage: obj.render(filepath) without return types