code: def test_if():
      x = relay.var("x", shape=(1, 16, 64, 64))
      y = relay.var("y", shape=(1, 16, 64, 64))
      cond = relay.var("cond", shape=(), dtype="uint1")
      net = relay.If(cond, x, y)
      net = relay.log(net)
      func = relay.Function(free_vars(net), net)
      func = run_infer_type(func)
      net = gradient(func, mode="higher_order")
      net = run_infer_type(net)
  
imports: import collections
  import numpy
  import pytest
  import tvm
  from tvm import te
  from tvm import relay
  from tvm.relay import GlobalVar
  from tvm.relay.analysis import free_vars, free_type_vars
  from tvm.relay import create_executor, transform
  from tvm.relay.transform import gradient
  from tvm.relay.prelude import Prelude
  from tvm.relay.testing import make_nat_expr, run_infer_type, check_grad, rand, count_ops
  import tvm.relay.op
label_desc: Use image node_id 19 for calling a global function with example usage: test_if() without return types