trailing whitespace

Author: Mehgarg

pandas/core/frame.py

@@ -350,6 +350,8 @@
     * "many_to_one" or "m:1": check if merge keys are unique in right
       dataset.
     * "many_to_many" or "m:m": allowed, but does not result in checks.
+preserve_index : str, optional
+ ____________
 
 Returns
 -------
@@ -8564,7 +8566,7 @@ def pivot(self, index=None, columns=None, values=None) -> DataFrame:
         margins : bool, default False
             Add all row / columns (e.g. for subtotal / grand totals).
         dropna : bool, default True
-            Do not include columns whose entries are all NaN. If true: 
+            Do not include columns whose entries are all NaN. If true:
             exclude rows containing missing data from aggregated margins.
         margins_name : str, default 'All'
             Name of the row / column that will contain the totals
@@ -10047,6 +10049,8 @@ def merge(
         copy: bool = True,
         indicator: bool = False,
         validate: str | None = None,
+        preserve_index: str | None = None,
+        
     ) -> DataFrame:
         from pandas.core.reshape.merge import merge
 
@@ -10064,6 +10068,7 @@ def merge(
             copy=copy,
             indicator=indicator,
             validate=validate,
+            preserve_index=preserve_index,
         )
 
     def round(