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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 quaternion_slerp(a, b, t):
 """Spherical linear interpolation for unit quaternions. This is based on the implementation in the gl-matrix package: https://github.com/toji/gl-matrix """

    if a is None:
        a = unit_quaternion()
    if b is None:
        b = unit_quaternion()
    # calc cosine
    cosom = np.dot(a, b)
    # adjust signs (if necessary)
    if cosom < 0.0:
        cosom = -cosom
        b = -b

    # calculate coefficients
    if (1.0 - cosom) > 0.000001:
        # standard case (slerp)
        omega = math.acos(cosom)
        sinom = math.sin(omega)
        scale0 = math.sin((1.0 - t) * omega) / sinom
        scale1 = math.sin(t * omega) / sinom
    else:
        # "from" and "to" quaternions are very close
        #  ... so we can do a linear interpolation
        scale0 = 1.0 - t
        scale1 = t
    return scale0 * a + scale1 * b