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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 distance(cls, q0, q1):
 """Quaternion intrinsic distance. Find the intrinsic 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 geodesic arc connecting q0 to q1. Note: Although the q0^(-1)*q1 != q1^(-1)*q0, the length of the path joining them is given by the logarithm of those product quaternions, the norm of which is the same. """

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