code: def test_hist_plot_1_dim(image_array_2bands):
      """A single dimensional array should plot properly."""
      array_1_dim = image_array_2bands.ravel()
      f, ax = ep.hist(array_1_dim)
      assert len(f.axes) == 1
      plt.close(f)
  
imports: import numpy
  import pytest
  import matplotlib.pyplot
  import earthpy.plot
label_desc: Use image node_id 13 for calling a global function with example usage: test_hist_plot_1_dim(image_array_2bands) without return types