code: def rbf_kernel(gamma, **kwargs):
      def f(x1, x2):
          distance = np.linalg.norm(x1 - x2) ** 2
          return np.exp(-gamma * distance)
  
      return f
  
label_desc: Use image node_id 3 for calling a global function with example usage: rbf_kernel(gamma) and returns: f, np