diff --git a/stdlib/2/calendar.pyi b/stdlib/2/calendar.pyi
index 045e912ca..54d3e45f0 100644
--- a/stdlib/2/calendar.pyi
+++ b/stdlib/2/calendar.pyi
@@ -1,4 +1,4 @@
-from typing import Any, Iterable, Optional, Tuple
+from typing import Any, Iterable, Optional, Tuple, Sequence
 import datetime
 
 LocaleType = Tuple[Optional[str], Optional[str]]
@@ -74,6 +74,12 @@ def format(cols: int, colwidth: int = ..., spacing: int = ...) -> str: ...
 def formatstring(cols: int, colwidth: int = ..., spacing: int = ...) -> str: ...
 def timegm(tuple: Tuple[int, ...]) -> int: ...
 
+# Data attributes
+day_name = ...  # type: Sequence[str]
+day_abbr = ...  # type: Sequence[str]
+month_name = ...  # type: Sequence[str]
+month_abbr = ...  # type: Sequence[str]
+
 # Below constants are not in docs or __all__, but enough people have used them
 # they are now effectively public.
 
diff --git a/stdlib/3/calendar.pyi b/stdlib/3/calendar.pyi
index 3901170ac..b0f8d988b 100644
--- a/stdlib/3/calendar.pyi
+++ b/stdlib/3/calendar.pyi
@@ -1,4 +1,4 @@
-from typing import Any, Iterable, Optional, Tuple
+from typing import Any, Iterable, Optional, Tuple, Sequence
 import datetime
 
 LocaleType = Tuple[Optional[str], Optional[str]]
@@ -74,6 +74,12 @@ def format(cols: int, colwidth: int = ..., spacing: int = ...) -> str: ...
 def formatstring(cols: int, colwidth: int = ..., spacing: int = ...) -> str: ...
 def timegm(tuple: Tuple[int, ...]) -> int: ...
 
+# Data attributes
+day_name = ...  # type: Sequence[str]
+day_abbr = ...  # type: Sequence[str]
+month_name = ...  # type: Sequence[str]
+month_abbr = ...  # type: Sequence[str]
+
 # Below constants are not in docs or __all__, but enough people have used them
 # they are now effectively public.