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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_push_pop():
 """Create pop and push nodes that are linked. Returns: A push and pop node which have `push_func` and `pop_func` annotations respectively, identifying them as such. They also have a `pop` and `push` annotation respectively, which links the push node to the pop node and vice versa. """

  push = copy.deepcopy(PUSH)
  pop = copy.deepcopy(POP)
  anno.setanno(push, 'pop', pop)
  anno.setanno(push, 'gen_push', True)
  anno.setanno(pop, 'push', push)
  op_id = _generate_op_id()
  return push, pop, op_id