Find the largest $A$ for which there exists a polynomial
$$
P(x)=A x^{4}+B x^{3}+C x^{2}+D x+E
$$
with real coefficients, which satisfies
$$
0<P(x)<1 \text { for }-1<x<1
$$

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