I need to write the equation of a curve which exactly goes throw point points:
$$\left(0,\frac{\pi ^2}{6}-1\right),\left(\frac{1}{2},\frac{2}{3}\right),\left(\frac{3}{4},\frac{2\pi}{3}-\frac{88}{63}\right),\left(1,\frac{3}{4}\right)$$ and the same values for negative arguments, i. e.
$$\left(-\frac{1}{2},\frac{2}{3}\right),\left(-\frac{3}{4},\frac{2\pi}{3}-\frac{88}{63}\right),\left(-1,\frac{3}{4}\right).$$