diff --git a/stdlib/2and3/datetime.pyi b/stdlib/2and3/datetime.pyi
index ea742b9cedd6..367b2a0d0014 100644
--- a/stdlib/2and3/datetime.pyi
+++ b/stdlib/2and3/datetime.pyi
@@ -93,6 +93,9 @@ class time:
     def microsecond(self) -> int: ...
     @property
     def tzinfo(self) -> Optional[_tzinfo]: ...
+    if sys.version_info >= (3, 6):
+        @property
+        def fold(self) -> int: ...
 
     def __le__(self, other: time) -> bool: ...
     def __lt__(self, other: time) -> bool: ...
@@ -108,8 +111,13 @@ class time:
     def utcoffset(self) -> Optional[timedelta]: ...
     def tzname(self) -> Optional[str]: ...
     def dst(self) -> Optional[int]: ...
-    def replace(self, hour: int = ..., minute: int = ..., second: int = ...,
-                microsecond: int = ..., tzinfo: Optional[_tzinfo] = ...) -> time: ...
+    if sys.version_info >= (3, 6):
+        def replace(self, hour: int = ..., minute: int = ..., second: int = ...,
+                    microsecond: int = ..., tzinfo: Optional[_tzinfo] = ...,
+                    *, fold: int = ...) -> time: ...
+    else:
+        def replace(self, hour: int = ..., minute: int = ..., second: int = ...,
+                    microsecond: int = ..., tzinfo: Optional[_tzinfo] = ...) -> time: ...
 
 _date = date
 _time = time
@@ -168,9 +176,14 @@ class datetime:
     max: ClassVar[datetime]
     resolution: ClassVar[timedelta]
 
-    def __init__(self, year: int, month: int, day: int, hour: int = ...,
-                 minute: int = ..., second: int = ..., microsecond: int = ...,
-                 tzinfo: Optional[tzinfo] = ...) -> None: ...
+    if sys.version_info >= (3, 6):
+        def __init__(self, year: int, month: int, day: int, hour: int = ...,
+                     minute: int = ..., second: int = ..., microsecond: int = ...,
+                     tzinfo: Optional[tzinfo] = ..., *, fold: int = ...) -> None: ...
+    else:
+        def __init__(self, year: int, month: int, day: int, hour: int = ...,
+                     minute: int = ..., second: int = ..., microsecond: int = ...,
+                     tzinfo: Optional[tzinfo] = ...) -> None: ...
 
     @property
     def year(self) -> int: ...
@@ -188,6 +201,9 @@ class datetime:
     def microsecond(self) -> int: ...
     @property
     def tzinfo(self) -> Optional[_tzinfo]: ...
+    if sys.version_info >= (3, 6):
+        @property
+        def fold(self) -> int: ...
 
     @classmethod
     def fromtimestamp(cls, t: float, tz: Optional[_tzinfo] = ...) -> datetime: ...
@@ -201,8 +217,12 @@ class datetime:
     def now(cls, tz: Optional[_tzinfo] = ...) -> datetime: ...
     @classmethod
     def utcnow(cls) -> datetime: ...
-    @classmethod
-    def combine(cls, date: date, time: time) -> datetime: ...
+    if sys.version_info >= (3, 6):
+        @classmethod
+        def combine(cls, date: date, time: time, tzinfo: Optional[_tzinfo] = ...) -> datetime: ...
+    else:
+        @classmethod
+        def combine(cls, date: date, time: time) -> datetime: ...
     def strftime(self, fmt: _Text) -> str: ...
     if sys.version_info >= (3,):
         def __format__(self, fmt: str) -> str: ...
@@ -216,9 +236,14 @@ class datetime:
     def date(self) -> _date: ...
     def time(self) -> _time: ...
     def timetz(self) -> _time: ...
-    def replace(self, year: int = ..., month: int = ..., day: int = ..., hour: int = ...,
-                minute: int = ..., second: int = ..., microsecond: int = ..., tzinfo:
-                Optional[_tzinfo] = ...) -> datetime: ...
+    if sys.version_info >= (3, 6):
+        def replace(self, year: int = ..., month: int = ..., day: int = ..., hour: int = ...,
+                    minute: int = ..., second: int = ..., microsecond: int = ..., tzinfo:
+                    Optional[_tzinfo] = ..., *, fold: int = ...) -> datetime: ...
+    else:
+        def replace(self, year: int = ..., month: int = ..., day: int = ..., hour: int = ...,
+                    minute: int = ..., second: int = ..., microsecond: int = ..., tzinfo:
+                    Optional[_tzinfo] = ...) -> datetime: ...
     if sys.version_info >= (3, 3):
         def astimezone(self, tz: Optional[_tzinfo] = ...) -> datetime: ...
     else: