Update type.md

Author: mtshiba

crates/ty_python_semantic/resources/mdtest/narrow/type.md

@@ -146,23 +146,19 @@ def _(x: A | B):
 
 ## No special narrowing for custom `type` callable
 
-`stub.pyi`:
-
-```pyi
-from ty_extensions import TypeOf
-
-def type(x: object) -> TypeOf[int]: ...
-```
-
 ```py
-from stub import type
+def type(x: object):
+    return int
 
 class A: ...
 class B: ...
 
 def _(x: A | B):
+    # The custom `type` function always returns `int`,
+    # so any branch other than `type(...) is int` is unreachable.
     if type(x) is A:
         reveal_type(x)  # revealed: Never
+    # And the condition here is always `True` and has no effect on the narrowing of `x`.
     elif type(x) is int:
         reveal_type(x)  # revealed: A | B
     else: