Add scentence really explaining B041

Author: cooperlees

README.rst

@@ -205,7 +205,7 @@ second usage. Save the result to a list if the result is needed multiple times.
 
 **B040**: Caught exception with call to ``add_note`` not used. Did you forget to ``raise`` it?
 
-**B041**: Repeated key-value pair in dictionary literal.
+**B041**: Repeated key-value pair in dictionary literal. Only emits errors when the key's value is *also* the same, being the opposite of the pyflakes like check.
 
 Opinionated warnings
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