Remove right associativity wording.

Follow-up to https://github.com/swaroopch/byte_of_python/pull/26

op_exp.md

@@ -165,7 +165,7 @@ There is an additional advantage to using parentheses - it helps us to change th
 
 ## Associativity
 
-Operators are usually associated from left to right. This means that operators with the same precedence are evaluated in a left to right manner. For example, `2 + 3 + 4` is evaluated as `(2 + 3) + 4`. Some operators like assignment operators have right to left associativity i.e. `a = b = c` is treated as `a = (b = c)`.
+Operators are usually associated from left to right. This means that operators with the same precedence are evaluated in a left to right manner. For example, `2 + 3 + 4` is evaluated as `(2 + 3) + 4`.
 
 ## Expressions