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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def upix_to_pix(upix):
 """Get the nside from a unique pixel number."""

    nside = np.power(2, np.floor(np.log2(upix / 4)) / 2).astype(int)
    pix = upix - 4 * np.power(nside, 2)
    return pix, nside