On the sides $BC$ and $CD$ of the square $ABCD$ with side length $1$, points $E$ and $F$ are chosen such that $\angle EAB = 20^\circ$ and $\angle EAF = 45^\circ$. Calculate the distance from point $A$ to the line $EF$.

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