replaced Appender with doc to support new docstring format

Author: smartvinnetou

pandas/core/frame.py

@@ -4734,20 +4734,20 @@ def _maybe_casted_values(index, labels=None):
     # ----------------------------------------------------------------------
     # Reindex-based selection methods
 
-    @Appender(_shared_docs["isna"] % _shared_doc_kwargs)
+    @doc(_shared_docs["isna"], **_shared_doc_kwargs)
     def isna(self) -> "DataFrame":
         result = self._constructor(self._data.isna(func=isna))
         return result.__finalize__(self, method="isna")
 
-    @Appender(_shared_docs["isna"] % _shared_doc_kwargs)
+    @doc(_shared_docs["isna"], **_shared_doc_kwargs)
     def isnull(self) -> "DataFrame":
         return self.isna()
 
-    @Appender(_shared_docs["notna"] % _shared_doc_kwargs)
+    @doc(_shared_docs["notna"], **_shared_doc_kwargs)
     def notna(self) -> "DataFrame":
         return ~self.isna()
 
-    @Appender(_shared_docs["notna"] % _shared_doc_kwargs)
+    @doc(_shared_docs["notna"], **_shared_doc_kwargs)
     def notnull(self) -> "DataFrame":
         return ~self.isna()