class_docstr: Tracing through optional input is not supported yet
class_docstr_tok: ["Tracing","through","optional","input","is","not","supported","yet"]
code: def forward(self, x, y=torch.ones(2, 3)):
      if y is not None:
          return x + y
      return x
  
imports: import torch
  from torch._export.db.case import export_case, SupportLevel
label_desc: Use image node_id 1 for calling the OptionalInput obj's underlying member method code with example usage: obj.forward(x, y) and returns: x, unknown