3. Let set $A=\{2,0,1,3\}$, set $B=\left\{x \mid -x \in A, 2-x^{2} \notin A\right\}$. Then the sum of all elements in set $B$ is $\qquad$.
$-x \in A \Rightarrow x=-2,0,-1,-3$, at this time $2-x^{2}=-2,2,1,-7$, so $B=\{-2,-3\}$. Therefore, the sum of all elements in set $B$ is -5.