diff --git a/stdlib/2/datetime.pyi b/stdlib/2/datetime.pyi
index f2d45d97e..eb915410c 100644
--- a/stdlib/2/datetime.pyi
+++ b/stdlib/2/datetime.pyi
@@ -3,7 +3,7 @@
 # NOTE: These are incomplete!
 
 from time import struct_time
-from typing import Optional, SupportsAbs, Tuple, Union, overload
+from typing import AnyStr, Optional, SupportsAbs, Tuple, Union, overload
 
 MINYEAR = 0
 MAXYEAR = 0
@@ -39,7 +39,7 @@ class date(object):
 
     def ctime(self) -> str: ...
     def strftime(self, fmt: Union[str, unicode]) -> str: ...
-    def __format__(self, fmt: Union[str, unicode]) -> str: ...
+    def __format__(self, fmt: AnyStr) -> AnyStr: ...
     def isoformat(self) -> str: ...
     def timetuple(self) -> struct_time: ...
     def toordinal(self) -> int: ...
@@ -84,7 +84,7 @@ class time:
     def __hash__(self) -> int: ...
     def isoformat(self) -> str: ...
     def strftime(self, fmt: Union[str, unicode]) -> str: ...
-    def __format__(self, fmt: str) -> str: ...
+    def __format__(self, fmt: AnyStr) -> AnyStr: ...
     def utcoffset(self) -> Optional[timedelta]: ...
     def tzname(self) -> Optional[str]: ...
     def dst(self) -> Optional[int]: ...
@@ -114,7 +114,7 @@ class timedelta(SupportsAbs[timedelta]):
     def __add__(self, other: timedelta) -> timedelta: ...
     def __radd__(self, other: timedelta) -> timedelta: ...
     def __sub__(self, other: timedelta) -> timedelta: ...
-    def __rsub(self, other: timedelta) -> timedelta: ...
+    def __rsub__(self, other: timedelta) -> timedelta: ...
     def __neg__(self) -> timedelta: ...
     def __pos__(self) -> timedelta: ...
     def __abs__(self) -> timedelta: ...
@@ -135,7 +135,7 @@ class timedelta(SupportsAbs[timedelta]):
     def __hash__(self) -> int: ...
 
 class datetime(object):
-    # TODO: is actually subclass of date, but __le__, __lt__, __ge__, __gt__ don't work with date.
+    # TODO: is actually subclass of date, but __le__, __lt__, __ge__, __gt__, __sub__ don't work with date.
     min = ...  # type: datetime
     max = ...  # type: datetime
     resolution = ...  # type: timedelta
@@ -176,7 +176,7 @@ class datetime(object):
     @classmethod
     def combine(cls, date: date, time: time) -> datetime: ...
     def strftime(self, fmt: Union[str, unicode]) -> str: ...
-    def __format__(self, fmt: str) -> str: ...
+    def __format__(self, fmt: AnyStr) -> AnyStr: ...
     def toordinal(self) -> int: ...
     def timetuple(self) -> struct_time: ...
     def utctimetuple(self) -> struct_time: ...
diff --git a/third_party/2/dateutil/relativedelta.pyi b/third_party/2/dateutil/relativedelta.pyi
index f910e9005..ea6592b1b 100644
--- a/third_party/2/dateutil/relativedelta.pyi
+++ b/third_party/2/dateutil/relativedelta.pyi
@@ -1,8 +1,11 @@
-from typing import Any, List, Optional, Union
+from typing import overload, Any, List, Optional, SupportsFloat, TypeVar, Union
 from datetime import date, datetime, timedelta
 
 __all__ = ...  # type: List[str]
 
+_SelfT = TypeVar('_SelfT', bound=relativedelta)
+_DateT = TypeVar('_DateT', date, datetime)
+
 
 class weekday(object):
     def __init__(self, weekday: int, n: Optional[int]=...) -> None: ...
@@ -49,38 +52,40 @@ class relativedelta(object):
     @weeks.setter
     def weeks(self, value: int) -> None: ...
 
-    def normalized(self) -> 'relativedelta': ...
+    def normalized(self: _SelfT) -> _SelfT: ...
 
-    def __add__(
-        self,
-        other: Union['relativedelta', timedelta, date, datetime]) -> 'relativedelta': ...
+    @overload
+    def __add__(self: _SelfT, other: relativedelta) -> _SelfT: ...
+    @overload
+    def __add__(self: _SelfT, other: timedelta) -> _SelfT: ...
+    @overload
+    def __add__(self, other: _DateT) -> _DateT: ...
+    @overload
+    def __radd__(self: _SelfT, other: timedelta) -> _SelfT: ...
+    @overload
+    def __radd__(self, other: _DateT) -> _DateT: ...
+    @overload
+    def __rsub__(self: _SelfT, other: timedelta) -> _SelfT: ...
+    @overload
+    def __rsub__(self, other: _DateT) -> _DateT: ...
+    def __sub__(self: _SelfT, other: relativedelta) -> _SelfT: ...
 
-    def __radd__(
-        self,
-        other: Any) -> 'relativedelta': ...
-
-    def __rsub__(
-        self,
-        other: Any) -> 'relativedelta': ...
-
-    def __sub__(self, other: 'relativedelta') -> 'relativedelta': ...
-
-    def __neg__(self) -> 'relativedelta': ...
+    def __neg__(self: _SelfT) -> _SelfT: ...
 
     def __bool__(self) -> bool: ...
 
     def __nonzero__(self) -> bool: ...
 
-    def __mul__(self, other: float) -> 'relativedelta': ...
+    def __mul__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...
 
-    def __rmul__(self, other: float) -> 'relativedelta': ...
+    def __rmul__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...
 
     def __eq__(self, other) -> bool: ...
 
     def __ne__(self, other: object) -> bool: ...
 
-    def __div__(self, other: float) -> 'relativedelta': ...
+    def __div__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...
 
-    def __truediv__(self, other: float) -> 'relativedelta': ...
+    def __truediv__(self: _SelfT, other: SupportsFloat) -> _SelfT: ...
 
     def __repr__(self) -> str: ...