Merge pull request #8857 from graingert/patch-1

Clarify encoding kwarg on to_csv

Author: jreback

pandas/core/frame.py

@@ -1137,8 +1137,8 @@ def to_csv(self, path_or_buf=None, sep=",", na_rep='', float_format=None,
         mode : str
             Python write mode, default 'w'
         encoding : string, optional
-            a string representing the encoding to use if the contents are
-            non-ascii, for python versions prior to 3
+            A string representing the encoding to use in the output file,
+            defaults to 'ascii' on Python 2 and 'utf-8' on Python 3.
         line_terminator : string, default '\\n'
             The newline character or character sequence to use in the output
             file