code: def test_get_png(self):
      analyzer = Analysis.objects.get(title="Pitch grapher")
  
      result = self.get_result(analyzer)
      self.assertEqual(result.data["file"][-4:], ".png")
  
imports: from timeside.server.models import *
  from timeside.server.tests.timeside_test_server import TimeSideTestServer
label_desc: Use image node_id 3 for calling the TestResults obj's underlying member method code with example usage: obj.test_get_png() without return types