code: def pointnormal(h):
      ROT = np.array([[0, -1], [1, 0]])
      p1 = np.array(h[0][:])
      p2 = np.array(h[1][:])
      n = (p2 - p1) / np.linalg.norm(p2 - p1)
      return p1, np.dot(ROT, n)
  
imports: import numpy
  import matplotlib.pyplot
  import numpy
  import matplotlib.image
label_desc: Use image node_id 1 for calling a global function with example usage: pointnormal(h) and returns: p1,  np