code: def klein(u, v):
      from math import pi, cos, sin
  
      if u < pi:
          x = 3 * cos(u) * (1 + sin(u)) + (2 * (1 - cos(u) / 2)) * cos(
              u
          ) * cos(v)
          z = -8 * sin(u) - 2 * (1 - cos(u) / 2) * sin(u) * cos(v)
      else:
          x = 3 * cos(u) * (1 + sin(u)) + (2 * (1 - cos(u) / 2)) * cos(
              v + pi
          )
          z = -8 * sin(u)
      y = -2 * (1 - cos(u) / 2) * sin(v)
      return x / 5, y / 5, z / 5
  
imports: import sys
  from vispy import app, scene
  from vispy.geometry.parametric import surface
label_desc: Use image node_id 1 for calling a global function with example usage: klein(u, v) and returns: unknown,  unknown,  unknown