code: def __call__(self, x):
      return sum(
          [
              a * self.kernel(x, x_repr)
              for x_repr, a in self.alphas.items()
          ],
          0.0,
      )
  
imports: from __future__ import print_function
  import autograd.numpy
  import autograd.numpy.random
  from autograd.extend import primitive, defvjp, defjvp, VSpace, Box
  from autograd.util import func
  from autograd import grad
label_desc: Use image node_id 2 for calling the RKHSFun obj's underlying member method code with example usage: obj.__call__(x) and returns: sum