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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 partial_transform(self, traj):
 """Featurize an MD trajectory into a vector space via pairwise atom-atom distances Parameters traj : mdtraj.Trajectory A molecular dynamics trajectory to featurize. Returns ------- features : np.ndarray, dtype=float, shape=(n_samples, n_features) A featurized trajectory is a 2D array of shape `(length_of_trajectory x n_features)` where each `features[i]` vector is computed by applying the featurization function to the `i`th snapshot of the input trajectory. See Also -------- transform : simultaneously featurize a collection of MD trajectories """

        d = md.geometry.compute_distances(traj, self.pair_indices,
                                          periodic=self.periodic)
        return d ** self.exponent