Let $\mathbb{Q}^+$ denote the set of positive rational numbers.  Let $f : \mathbb{Q}^+ \to \mathbb{Q}^+$ be a function such that
\[f \left( x + \frac{y}{x} \right) = f(x) + \frac{f(y)}{f(x)} + 2y\]for all $x,$ $y \in \mathbb{Q}^+.$

Find all possible values of $f \left( \frac{1}{3} \right).$  Enter all the possible values, separated by commas.The answer is in the form rac{m}{n}, where gcd(m, n) = 1. Please provide the value of m + n.

Let's think step by step and output the final answer within \boxed{}.
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