code: def test_plot_normalize():
      a = np.linspace(1, 6, 10)
      b = adjust_band(a, "linear")
      np.testing.assert_array_almost_equal(np.linspace(0, 1, 10), b)
  
imports: import pytest
  import matplotlib
  import numpy
  import rasterio
  from rasterio.plot import show, show_hist, get_plt, plotting_extent, adjust_band
  from rasterio.enums import ColorInterp
label_desc: Use image node_id 20 for calling a global function with example usage: test_plot_normalize() without return types