code: def grayscale(frame):
      return skimage.util.img_as_ubyte(skimage.color.rgb2gray(frame))
  
file_path: SerpentAI/serpent/frame_transformer.py
imports: import skimage.transform
  import skimage.color
  import skimage.util
  from PIL import Image
  import io
label_desc: Use image node_id 5 for calling the FrameTransformer obj's underlying member method code with example usage: obj.grayscale(frame) and returns: skimage