Stumbling around on the complex plane

Discrete Mathematics Level pending

Let $$C$$ be the constant term of:

$(x^{1+\mathrm{i}}+x^{1-\mathrm{i}}+x^{-1+\mathrm{i}}+x^{-1-\mathrm{i}})^{14}$

What is $$\sqrt{C}$$?

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