code: def test_diamond():
      x = np.array([0.0, 1.0, 0.0, -1.0, 0.0])
      y = np.array([1.0, 0.0, -1.0, 0.0, 1.0])
  
      fig, ax = plt.subplots()
      ax.plot(x, y)
      ax.set_xlim(-0.6, 0.6)
      ax.set_ylim(-0.6, 0.6)
  
imports: import base64
  import io
  import numpy
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  import pytest
  from matplotlib.testing.decorators import check_figures_equal, image_comparison, remove_ticks_and_titles
  import matplotlib.pyplot
  from matplotlib import patches, transforms
  from matplotlib.path import Path
label_desc: Use image node_id 3 for calling a global function with example usage: test_diamond() without return types