diff --git a/builtins/2and3/_codecs.pyi b/builtins/2.7/_codecs.pyi
similarity index 100%
rename from builtins/2and3/_codecs.pyi
rename to builtins/2.7/_codecs.pyi
diff --git a/builtins/3/_codecs.pyi b/builtins/3/_codecs.pyi
new file mode 100644
index 000000000..b2f7a1a93
--- /dev/null
+++ b/builtins/3/_codecs.pyi
@@ -0,0 +1,51 @@
+"""Stub file for the '_codecs' module."""
+
+from typing import Any, AnyStr, Callable, Tuple, Optional
+
+import codecs
+
+# For convenience:
+_Handler = Callable[[Exception], Tuple[str, int]]
+
+def register(search_function: Callable[[str], Any]) -> None: ...
+def register_error(errors: str, handler: _Handler) -> None: ...
+def lookup(a: str) -> codecs.CodecInfo: ...
+def lookup_error(a: str) -> _Handler: ...
+def decode(obj: Any, encoding:str = ..., errors:str = ...) -> Any: ...
+def encode(obj: Any, encoding:str = ..., errors:str = ...) -> Any: ...
+def charmap_build(a: str) -> Dict[int, int]: ...
+
+def ascii_decode(data: AnyStr, errors:str = ...) -> Tuple[str, int]: ...
+def ascii_encode(data: AnyStr, errors:str = ...) -> Tuple[bytes, int]: ...
+def charbuffer_encode(data: AnyStr, errors: str = ...) -> Tuple[bytes, int]: ...
+def charmap_decode(data: AnyStr, errors: str = ..., mapping: Optional[Dict[int, int]] = ...) -> Tuple[str, int]: ...
+def charmap_encode(data: AnyStr, errors: str, mapping: Optional[Dict[int, int]] = ...) -> Tuple[bytes, int]: ...
+def escape_decode(data: AnyStr, errors:str = ...) -> Tuple[str, int]: ...
+def escape_encode(data: AnyStr, errors:str = ...) -> Tuple[bytes, int]: ...
+def latin_1_decode(data: AnyStr, errors:str = ...) -> Tuple[str, int]: ...
+def latin_1_encode(data: AnyStr, errors:str = ...) -> Tuple[bytes, int]: ...
+def raw_unicode_escape_decode(data: AnyStr, errors:str = ...) -> Tuple[str, int]: ...
+def raw_unicode_escape_encode(data: AnyStr, errors:str = ...) -> Tuple[bytes, int]: ...
+def readbuffer_encode(data: AnyStr, errors:str = ...) -> Tuple[bytes, int]: ...
+def unicode_escape_decode(data: AnyStr, errors:str = ...) -> Tuple[str, int]: ...
+def unicode_escape_encode(data: AnyStr, errors:str = ...) -> Tuple[bytes, int]: ...
+def unicode_internal_decode(data: AnyStr, errors:str = ...) -> Tuple[str, int]: ...
+def unicode_internal_encode(data: AnyStr, errors:str = ...) -> Tuple[bytes, int]: ...
+def utf_16_be_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_16_be_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...
+def utf_16_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_16_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...
+def utf_16_ex_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_16_le_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_16_le_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...
+def utf_32_be_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_32_be_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...
+def utf_32_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_32_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...
+def utf_32_ex_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_32_le_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_32_le_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...
+def utf_7_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_7_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...
+def utf_8_decode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[str, int]: ...
+def utf_8_encode(data: AnyStr, errors:str = ..., final:int = ...) -> Tuple[bytes, int]: ...