DOC: added .join to 'see also' in Series.str.cat (pandas-dev#22175)

Author: ym-pett

pandas/core/strings.py

@@ -2065,6 +2065,7 @@ def cat(self, others=None, sep=None, na_rep=None, join=None):
         See Also
         --------
         split : Split each string in the Series/Index
+        join : Join lists contained as elements in the Series/Index
 
         Examples
         --------