code: def test_ax_1d():
      fig, ax = plt.subplots(1, 1)
      out_ax = Rank1D().feature_ranks(X)
      assert ax is not out_ax
      out_ax = Rank1D(ax=ax).feature_ranks(X)
      assert ax is out_ax
  
imports: import matplotlib.pyplot
  import pytest
  import pandas
  import numpy
  from sklearn.datasets import load_iris
  from matplotlib.testing.decorators import image_comparison
  from sklearn_evaluation.plot import Rank1D, Rank2D
label_desc: Use image node_id 13 for calling a global function with example usage: test_ax_1d() without return types