Fix string concatenation with non-string (#102728)

Signed-off-by: Edward Z. Yang <ezyang@meta.com>

Pull Request resolved: https://github.com/pytorch/pytorch/pull/102728
Approved by: https://github.com/Skylion007
diff --git a/torch/_dynamo/utils.py b/torch/_dynamo/utils.py
index 32f76da..c30a1e0 100644
--- a/torch/_dynamo/utils.py
+++ b/torch/_dynamo/utils.py
@@ -1525,7 +1525,7 @@
         except ImportError:
             return (
                 "Tabulate module missing, please install tabulate to log the graph in tabular format, logging code instead:\n"
-                + format_graph_code(fn_name, gm)
+                + str(lazy_format_graph_code(fn_name, gm))
             )
 
         node_specs = [