Two congruent circles centered at points $A$ and $B$ each pass through the other circle's center. The line containing both $A$ and $B$ is extended to intersect the circles at points $C$ and $D$. The circles intersect at two points, one of which is $E$. What is the degree measure of $\angle CED$? If the answer is $x^\circ$, what is the value of $x$?

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