code: def test_scale_continuous_with_non_color_aesthetic():
      spec = gg.scale_continuous("x")
      as_dict = spec.as_dict()
      assert as_dict["aesthetic"] == "x"
      assert "scale_mapper_kind" not in as_dict
  
imports: import pytest
  import lets_plot
  from lets_plot.plot.core import FeatureSpec
  from lets_plot.plot.core import FeatureSpecArray
  from lets_plot.plot.scale import _scale
label_desc: Use image node_id 17 for calling a global function with example usage: test_scale_continuous_with_non_color_aesthetic() without return types