code: def test_sorts_by_x():
      data = pd.DataFrame({"x": [5, 0, 1, 2, 3, 4], "y": range(6)})
      p = ggplot(data, aes("x", "y")) + geom_smooth(stat="identity")
  
      assert p == "sorts_by_x"
  
imports: import numpy
  import pandas
  import pytest
  import statsmodels.api
  from plotnine import aes, coord_trans, geom_point, geom_smooth, ggplot, stat_smooth
  from plotnine.exceptions import PlotnineWarning
label_desc: Use image node_id 10 for calling a global function with example usage: test_sorts_by_x() without return types