Update README.md

Author: fabiocaccamo

README.md

@@ -130,7 +130,7 @@ d.keyattr_dynamic = True
 > **Warning** - even if this feature is very useful, it has some obvious limitations: it works only for string keys that are *unprotected* (not starting with an `_`) and that don't clash with the currently supported methods names.
 
 ### Keylist
-Wherever a **key** is used, it is possible to use also a **list (or a tuple) of keys**.
+Wherever a **key** is used, it is possible to use also a **list of keys**.
 
 ```python
 d = benedict()