diff --git a/third_party/3/pyrfc3339/__init__.pyi b/third_party/3/pyrfc3339/__init__.pyi
new file mode 100644
index 000000000..d8c1ca5e8
--- /dev/null
+++ b/third_party/3/pyrfc3339/__init__.pyi
@@ -0,0 +1,2 @@
+from .generator import generate as generate
+from .parser import parse as parse
diff --git a/third_party/3/pyrfc3339/generator.pyi b/third_party/3/pyrfc3339/generator.pyi
new file mode 100644
index 000000000..9375b5b61
--- /dev/null
+++ b/third_party/3/pyrfc3339/generator.pyi
@@ -0,0 +1,3 @@
+from datetime import datetime
+
+def generate(dt: datetime, utc: bool = ..., accept_naive: bool = ..., microseconds: bool = ...) -> str: ...
diff --git a/third_party/3/pyrfc3339/parser.pyi b/third_party/3/pyrfc3339/parser.pyi
new file mode 100644
index 000000000..445b542c3
--- /dev/null
+++ b/third_party/3/pyrfc3339/parser.pyi
@@ -0,0 +1,3 @@
+from datetime import datetime
+
+def parse(timestamp: str, utc: bool = ..., produce_naive: bool = ...) -> datetime: ...
diff --git a/third_party/3/pyrfc3339/utils.pyi b/third_party/3/pyrfc3339/utils.pyi
new file mode 100644
index 000000000..f49a8c068
--- /dev/null
+++ b/third_party/3/pyrfc3339/utils.pyi
@@ -0,0 +1,11 @@
+from datetime import datetime, timedelta, tzinfo
+from typing import Optional
+
+class FixedOffset(tzinfo):
+    def __init__(self, hours: float, minutes: float) -> None: ...
+    def dst(self, dt: Optional[datetime]) -> timedelta: ...
+    def utcoffset(self, dt: Optional[datetime]) -> timedelta: ...
+    def tzname(self, dt: Optional[datetime]) -> str: ...
+
+def timedelta_seconds(td: timedelta) -> int: ...
+def timezone(utcoffset: float) -> str: ...