code: def test_let_polymorphism():
      id = relay.Var("id")
      xt = relay.TypeVar("xt")
      x = relay.Var("x", xt)
      body = relay.Tuple([id(relay.const(1)), id(relay.Tuple([]))])
      body = relay.Let(id, relay.Function([x], x, xt, [xt]), body)
      body = infer_expr(body)
      int32 = relay.TensorType((), "int32")
      tvm.ir.assert_structural_equal(
          body.checked_type,
          relay.TupleType([int32, relay.TupleType([])]),
      )
  
imports: import pytest
  import tvm
  from tvm import IRModule, parser, relay, te
  from tvm.relay import analysis, op, transform
  from tvm.relay.op import op
  import numpy
label_desc: Use image node_id 25 for calling a global function with example usage: test_let_polymorphism() without return types