DOC: Include timedelta as freq for timedelta_range, interval_range, and date_range

pandas/core/indexes/datetimes.py

@@ -790,7 +790,7 @@ def date_range(
         Right bound for generating dates.
     periods : int, optional
         Number of periods to generate.
-    freq : str, datetime.timedelta, or DateOffset, default 'D'
+    freq : str, Timedelta, datetime.timedelta, or DateOffset, default 'D'
         Frequency strings can have multiples, e.g. '5H'. See
         :ref:`here <timeseries.offset_aliases>` for a list of
         frequency aliases.

pandas/core/indexes/interval.py

@@ -991,7 +991,7 @@ def interval_range(
         Right bound for generating intervals.
     periods : int, default None
         Number of periods to generate.
-    freq : numeric, str, datetime.timedelta, or DateOffset, default None
+    freq : numeric, str, Timedelta, datetime.timedelta, or DateOffset, default None
         The length of each interval. Must be consistent with the type of start
         and end, e.g. 2 for numeric, or '5H' for datetime-like.  Default is 1
         for numeric and 'D' for datetime-like.

pandas/core/indexes/timedeltas.py

@@ -246,7 +246,7 @@ def timedelta_range(
         Right bound for generating timedeltas.
     periods : int, default None
         Number of periods to generate.
-    freq : str or DateOffset, default 'D'
+    freq : str, Timedelta, datetime.timedelta, or DateOffset, default 'D'
         Frequency strings can have multiples, e.g. '5H'.
     name : str, default None
         Name of the resulting TimedeltaIndex.