code: def test_scalar_trace_as_data(self):
      fig = go.Figure(data=go.Waterfall(y=[2, 1, 3]))
      self.assertEqual(fig.data, (go.Waterfall(y=[2, 1, 3]),))
  
      fig = go.Figure(data=dict(type="waterfall", y=[2, 1, 3]))
      self.assertEqual(fig.data, (go.Waterfall(y=[2, 1, 3]),))
  
imports: import plotly.graph_objects
  from plotly.subplots import make_subplots
  from plotly.tests.utils import TestCaseNoTemplate
  import pytest
label_desc: Use image node_id 12 for calling the FigureTest obj's underlying member method code with example usage: obj.test_scalar_trace_as_data() without return types