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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 describe_features(self, traj):
 """Generic method for describing features. Parameters traj : mdtraj.Trajectory Trajectory to use Returns ------- feature_descs : list of dict Dictionary describing each feature with the following information about the atoms participating in each feature - resnames: unique names of residues - atominds: the four atom indicies - resseqs: unique residue sequence ids (not necessarily 0-indexed) - resids: unique residue ids (0-indexed) - featurizer: Featurizer name - featuregroup: Other information Notes ------- Method resorts to returning N/A for everything if describe_features in not implemented in the sub_class """

        n_f = self.partial_transform(traj).shape[1]
        zippy=zip(itertools.repeat("N/A", n_f),
                  itertools.repeat("N/A", n_f),
                  itertools.repeat("N/A", n_f),
                  itertools.repeat(("N/A","N/A","N/A","N/A"), n_f))

        return dict_maker(zippy)