add some missing freq annotations#

Author: MarcoGorelli

pandas-stubs/core/frame.pyi

@@ -1684,14 +1684,14 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
     ) -> Self: ...
     def to_timestamp(
         self,
-        freq=...,
+        freq: Frequency | None = None,
         how: ToTimestampHow = ...,
         axis: Axis = 0,
         copy: _bool = True,
     ) -> Self: ...
     def to_period(
         self,
-        freq: _str | None = None,
+        freq: Frequency | None = None,
         axis: Axis = 0,
         copy: _bool = True,
     ) -> Self: ...

pandas-stubs/core/groupby/groupby.pyi

@@ -319,7 +319,7 @@ class GroupBy(BaseGroupBy[NDFrameT]):
         periods: int = ...,
         fill_method: Literal["bfill", "ffill"] | None | _NoDefaultDoNotUse = ...,
         limit: int | None | _NoDefaultDoNotUse = ...,
-        freq=...,
+        freq: Frequency | None = None,
         axis: Axis | _NoDefaultDoNotUse = ...,
     ) -> NDFrameT: ...
     @final

pandas-stubs/core/series.pyi

@@ -1237,7 +1237,7 @@ class Series(IndexOpsMixin[S1], NDFrame):
     ) -> Series[S1]: ...
     def to_timestamp(
         self,
-        freq=...,
+        freq: Frequency | None = None,
         how: ToTimestampHow = "start",
         copy: _bool = True,
     ) -> Series[S1]: ...