diff --git a/compiler/erg_compiler/lib/pystd/collections.d/abc.d.er b/compiler/erg_compiler/lib/pystd/collections.d/abc.d.er
index 309d73c1..3f430fe8 100644
--- a/compiler/erg_compiler/lib/pystd/collections.d/abc.d.er
+++ b/compiler/erg_compiler/lib/pystd/collections.d/abc.d.er
@@ -1,13 +1,12 @@
-.Container = Trait { .__contains__ = (self: Self) -> Bool }
-.Hashable = Trait { .__hash__ = (self: Self) -> Nat }
-.Sized = Trait { .__len__ = (self: Self) -> Nat }
-# TODO: varargs
-.Callable = Trait { .__call__ = (self: Self) -> Obj }
-# .Iterable T = Trait { .__iter__ = (self: Self) -> Iterator T }
-.Iterable = Trait { .__iter__ = (self: Self) -> .Iterator }
-.Collection = Subsume .Container and .Iterable
-# .Iterator T = Trait { .__next__ = (self: Self) -> T }
-.Iterator = Trait { .__next__ = (self: Self) -> Obj }
-.Reversible = Trait { .__reversed__ = (self: Self) -> .Iterator }
-.Genertor = Subsume .Iterator
-.Sequence = Subsume .Collection and .Sized and .Reversible
+# The ABCs in this file are not defined as a collection of traits.
+# Use `std/abc` instead.
+.Container: ClassType
+.Hashable: ClassType
+.Sized: ClassType
+.Callable: ClassType
+.Iterable: ClassType
+.Collection: ClassType
+.Iterator: ClassType
+.Reversible: ClassType
+.Genertor: ClassType
+.Sequence: ClassType
diff --git a/compiler/erg_compiler/lib/std/abc.er b/compiler/erg_compiler/lib/std/abc.er
new file mode 100644
index 00000000..309d73c1
--- /dev/null
+++ b/compiler/erg_compiler/lib/std/abc.er
@@ -0,0 +1,13 @@
+.Container = Trait { .__contains__ = (self: Self) -> Bool }
+.Hashable = Trait { .__hash__ = (self: Self) -> Nat }
+.Sized = Trait { .__len__ = (self: Self) -> Nat }
+# TODO: varargs
+.Callable = Trait { .__call__ = (self: Self) -> Obj }
+# .Iterable T = Trait { .__iter__ = (self: Self) -> Iterator T }
+.Iterable = Trait { .__iter__ = (self: Self) -> .Iterator }
+.Collection = Subsume .Container and .Iterable
+# .Iterator T = Trait { .__next__ = (self: Self) -> T }
+.Iterator = Trait { .__next__ = (self: Self) -> Obj }
+.Reversible = Trait { .__reversed__ = (self: Self) -> .Iterator }
+.Genertor = Subsume .Iterator
+.Sequence = Subsume .Collection and .Sized and .Reversible