replaced Appender with doc

Author: smartvinnetou

pandas/core/generic.py

@@ -10687,17 +10687,17 @@ def _doc_parms(cls):
 """
 
 _num_ddof_doc = """
-%(desc)s
+{desc}
 
 Parameters
 ----------
-axis : %(axis_descr)s
+axis : {axis_descr}
 skipna : bool, default True
     Exclude NA/null values. If an entire row/column is NA, the result
     will be NA.
 level : int or level name, default None
     If the axis is a MultiIndex (hierarchical), count along a
-    particular level, collapsing into a %(name1)s.
+    particular level, collapsing into a {name1}.
 ddof : int, default 1
     Delta Degrees of Freedom. The divisor used in calculations is N - ddof,
     where N represents the number of elements.
@@ -10707,7 +10707,7 @@ def _doc_parms(cls):
 
 Returns
 -------
-%(name1)s or %(name2)s (if level specified)\n"""
+{name1} or {name2} (if level specified)\n"""
 
 _bool_doc = """
 %(desc)s
@@ -11410,8 +11410,7 @@ def stat_func(
 def _make_stat_function_ddof(
     cls, name: str, name1: str, name2: str, axis_descr: str, desc: str, func: Callable
 ) -> Callable:
-    @Substitution(desc=desc, name1=name1, name2=name2, axis_descr=axis_descr)
-    @Appender(_num_ddof_doc)
+    @doc(_num_ddof_doc, desc=desc, name1=name1, name2=name2, axis_descr=axis_descr)
     def stat_func(
         self, axis=None, skipna=None, level=None, ddof=1, numeric_only=None, **kwargs
     ):