CLN: remove redundant variable in setitem_with_indexer (pandas-dev#37563)

Author: jbrockmendel

pandas/core/indexing.py

@@ -1645,19 +1645,14 @@ def _setitem_with_indexer_split_path(self, indexer, value):
         if isinstance(value, ABCSeries):
             value = self._align_series(indexer, value)
 
-        info_idx = indexer[1]
-        if is_integer(info_idx):
-            info_idx = [info_idx]
-        labels = self.obj.columns[info_idx]
-
         # Ensure we have something we can iterate over
         ilocs = self._ensure_iterable_column_indexer(indexer[1])
 
         plane_indexer = indexer[:1]
         lplane_indexer = length_of_indexer(plane_indexer[0], self.obj.index)
         # lplane_indexer gives the expected length of obj[indexer[0]]
 
-        if len(labels) == 1:
+        if len(ilocs) == 1:
             # We can operate on a single column
 
             # require that we are setting the right number of values that
@@ -1678,20 +1673,20 @@ def _setitem_with_indexer_split_path(self, indexer, value):
             if isinstance(value, ABCDataFrame):
                 self._setitem_with_indexer_frame_value(indexer, value)
 
-            # we have an equal len ndarray/convertible to our labels
+            # we have an equal len ndarray/convertible to our ilocs
             # hasattr first, to avoid coercing to ndarray without reason.
             # But we may be relying on the ndarray coercion to check ndim.
             # Why not just convert to an ndarray earlier on if needed?
             elif np.ndim(value) == 2:
                 self._setitem_with_indexer_2d_value(indexer, value)
 
             elif (
-                len(labels) == 1
+                len(ilocs) == 1
                 and lplane_indexer == len(value)
                 and not is_scalar(plane_indexer[0])
             ):
                 # we have an equal len list/ndarray
-                # We only get here with len(labels) == len(ilocs) == 1
+                # We only get here with len(ilocs) == 1
                 self._setitem_single_column(ilocs[0], value, plane_indexer)
 
             elif lplane_indexer == 0 and len(value) == len(self.obj.index):