typo fix

Author: zyuhel

Notes/02_Working_with_data/07_Objects.md

@@ -238,7 +238,7 @@ items[1].sqrt(2)    # math
 except items[2]:    # ValueError
 ```
 
-With great power come responsibility.  Just because you can do that doesn't me you should.
+With great power come responsibility.  Just because you can do that doesn't mean you should.
 
 ## Exercises