code: def enhance_edges_prewitt(image, mask=None, direction="all"):
      if direction.casefold() == "all":
          output_pixels = centrosome.filter.prewitt(image, mask)
      elif direction.casefold() == "horizontal":
          output_pixels = centrosome.filter.hprewitt(image, mask)
      elif direction.casefold() == "vertical":
          output_pixels = centrosome.filter.vprewitt(image, mask)
      else:
          raise NotImplementedError(
              f"Unimplemented direction for Prewitt: {direction}"
          )
      return output_pixels
  
imports: import numpy
  import skimage.color
  import skimage.morphology
  import centrosome
  import centrosome.threshold
  import scipy
  import matplotlib
label_desc: Use image node_id 5 for calling a global function with example usage: enhance_edges_prewitt(image, mask, direction) and returns: output_pixels