code: def test_line():
      data2 = data.copy()
  
      # geom_path plots in given order. geom_line &
      # geom_step sort by x before plotting
      data2["x"] = data["x"].to_numpy()[::-1]
  
      p = (
          ggplot(data2, aes("x"))
          + geom_path(aes(y="y"), size=4)
          + geom_line(aes(y="y+2"), color="blue", size=4)
          + geom_step(aes(y="y+4"), color="red", size=4)
      )
  
      assert p == "path_line_step"
  
file_path: plotnine/tests/test_geom_path_line_step.py
imports: import numpy
  import pandas
  import pytest
  from plotnine import aes, arrow, facet_grid, geom_line, geom_path, geom_point, geom_step, ggplot
  from plotnine.exceptions import PlotnineWarning
label_desc: Use image node_id 6 for calling a global function with example usage: test_line() without return types