fix summary

Author: MarcoGorelli

pandas/core/arrays/datetimes.py

@@ -1328,7 +1328,7 @@ def date(self) -> npt.NDArray[np.object_]:
 
     def isocalendar(self) -> DataFrame:
         """
-        Returns a DataFrame with the year, week, and day calculated according to
+        Return a DataFrame with the year, week, and day calculated according to
         the ISO 8601 standard.
 
         .. versionadded:: 1.1.0

pandas/core/indexes/accessors.py

@@ -243,7 +243,7 @@ def freq(self):
 
     def isocalendar(self):
         """
-        Returns a DataFrame with the year, week, and day calculated according to
+        Return a DataFrame with the year, week, and day calculated according to
         the ISO 8601 standard.
 
         .. versionadded:: 1.1.0