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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 sym_distance(cls, q0, q1):
 """Quaternion symmetrized distance. Find the intrinsic symmetrized geodesic distance between q0 and q1. Params: q0: the first quaternion q1: the second quaternion Returns: A positive amount corresponding to the length of the symmetrized geodesic curve connecting q0 to q1. Note: This formulation is more numerically stable when performing iterative gradient descent on the Riemannian quaternion manifold. However, the distance between q and -q is equal to pi, rendering this formulation not useful for measuring rotation similarities when the samples are spread over a "solid" angle of more than pi/2 radians (the spread refers to quaternions as point samples on the unit hypersphere). """

        q = Quaternion.sym_log_map(q0, q1)
        return q.norm