Switch to_timedelta argument type from list to Sequence (#959)

* GH 956 Allowing sequence type in to_timedelta

* GH 956 PR feedback

* GH 956 PR feedback

* GH 956 PR feedback

* Update tests/test_timefuncs.py

Co-authored-by: Irv Lustig <[email protected]>

* Fixing lint issue

---------

Co-authored-by: Irv Lustig <[email protected]>

Author: loicdiridollou

pandas-stubs/core/tools/timedeltas.pyi

@@ -14,6 +14,7 @@ from pandas._libs.tslibs.timedeltas import TimeDeltaUnitChoices
 from pandas._typing import (
     ArrayLike,
     RaiseCoerce,
+    SequenceNotStr,
 )
 
 @overload
@@ -31,8 +32,8 @@ def to_timedelta(
 @overload
 def to_timedelta(
     arg: (
-        Sequence[float | timedelta]
-        | list[str | float | timedelta]
+        SequenceNotStr
+        | Sequence[float | timedelta]
         | tuple[str | float | timedelta, ...]
         | range
         | ArrayLike

tests/test_timefuncs.py

@@ -140,6 +140,11 @@ def test_timedelta_series_arithmetic() -> None:
     r4: pd.TimedeltaIndex = tds1 / 10.2
 
 
+def test_timedelta_series_string() -> None:
+    seq_list = ["1 day"]
+    check(assert_type(pd.to_timedelta(seq_list), pd.TimedeltaIndex), pd.TimedeltaIndex)
+
+
 def test_timestamp_timedelta_series_arithmetic() -> None:
     ts1 = pd.to_datetime(pd.Series(["2022-03-05", "2022-03-06"]))
     assert isinstance(ts1.iloc[0], pd.Timestamp)