diff --git a/graphene/utils/deprecated.py b/graphene/utils/deprecated.py
index 42c358fb..242a0c65 100644
--- a/graphene/utils/deprecated.py
+++ b/graphene/utils/deprecated.py
@@ -24,6 +24,7 @@ def deprecated(reason):
         #    @deprecated("please, use another function")
         #    def old_function(x, y):
         #      pass
+        reason = reason.decode() if isinstance(reason, bytes) else reason
 
         def decorator(func1):
             if inspect.isclass(func1):
diff --git a/tox.ini b/tox.ini
index fdec66d0..f172b5fe 100644
--- a/tox.ini
+++ b/tox.ini
@@ -22,7 +22,7 @@ commands =
 [testenv:mypy]
 basepython = python3.10
 deps =
-    mypy>=0.950,<1
+    mypy>=1.10,<2
 commands =
     mypy graphene