docstr: Test type annotations in the forward function.
  The annotation should appear in the n.graph
  where n is the corresponding node in the resulting graph.
code: def test_annotations(self):
      """
      Test type annotations in the forward function.
      The annotation should appear in the n.graph
      where n is the corresponding node in the resulting graph.
      """
  
      class M(torch.nn.Module):
          def forward(
              self,
              x: TensorType((1, 2, 3, Dyn)),
              y: Dyn,
              z: TensorType[Dyn, 3, Dyn],
          ):
              return torch.add(x, y) + z
  
      module = M()
      symbolic_traced: torch.fx.GraphModule = symbolic_trace(module)
  
      expected_ph_types = [
          TensorType((1, 2, 3, Dyn)),
          Dyn,
          TensorType((Dyn, 3, Dyn)),
      ]
      expected_iter = iter(expected_ph_types)
  
      for n in symbolic_traced.graph.nodes:
          if n.op == "placeholder":
              assert n.type == next(expected_iter)
  
imports: import unittest
  import torch
  from torch.fx import symbolic_trace
  from torch.fx.experimental.unify_refinements import infer_symbolic_types
  from torch.fx.experimental.refinement_types import Equality
  from torch.fx.tensor_type import TensorType, Dyn, is_consistent, is_more_precise
  from torch.fx.annotate import annotate
  from torch.fx.experimental.graph_gradual_typechecker import GraphTypeChecker, broadcast_types, Refine
  from torch.fx.experimental.rewriter import RewritingTracer
  from torch.fx import GraphModule
  from torch.fx.passes.shape_prop import ShapeProp
  from torch.testing._internal.common_utils import TestCase
  import sympy
label_desc: Use image node_id 1 for calling the AnnotationsTest obj's underlying member method code with example usage: obj.test_annotations() and returns: unknown