code: def listed_cmap():
      cmap = ListedColormap(
          ["white", "tan", "purple", "springgreen", "darkgreen"]
      )
      norm = mpl.colors.Normalize(vmin=1, vmax=5)
      return cmap, norm
  
imports: import numpy
  import pytest
  import matplotlib
  import matplotlib.pyplot
  from matplotlib.colors import ListedColormap
  import earthpy.plot
label_desc: Use image node_id 1 for calling a global function with example usage: listed_cmap() and returns: cmap,  norm