DOC: Add Returns and Notes sections to docstring.

Author: dahlbaek

pandas/core/series.py

@@ -2920,6 +2920,18 @@ def to_csv(self, path_or_buf=None, index=True, sep=",", na_rep='',
         kwargs
             Additional keyword arguments are passed to
             :func:`pandas.DataFrame.to_csv`
+
+        Returns
+        -------
+        None or string
+            If path_or_buf is None, returns the result as a string, otherwise
+            returns None.
+
+        Notes
+        -----
+        Constructs a DataFrame using :func:`~pandas.Series.to_frame`, then
+        calls the method :func:`pandas.DataFrame.to_csv` on that DataFrame.
+
         """
 
         # convert to DataFrame