DOC: update the pandas.DataFrame.apply docstring

Author: mdeboc

pandas/core/frame.py

@@ -4882,7 +4882,7 @@ def apply(self, func, axis=0, broadcast=None, raw=False, reduce=None,
               of the DataFrame, the original index and columns will be
               retained.
 
-            The default behaviour (`None`) depends on the return value of the
+            The default behaviour `None` depends on the return value of the
             applied function: list-like results will be returned as a Series
             of those. However if the apply function returns a Series these
             are expanded to columns.