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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 to_trajectory(self, show_ports=False, chains=None, residues=None, box=None):
 """Convert to an md.Trajectory and flatten the compound. Parameters show_ports : bool, optional, default=False Include all port atoms when converting to trajectory. chains : mb.Compound or list of mb.Compound Chain types to add to the topology residues : str of list of str Labels of residues in the Compound. Residues are assigned by checking against Compound.name. box : mb.Box, optional, default=self.boundingbox (with buffer) Box information to be used when converting to a `Trajectory`. If 'None', a bounding box is used with a 0.5nm buffer in each dimension. to avoid overlapping atoms, unless `self.periodicity` is not None, in which case those values are used for the box lengths. Returns ------- trajectory : md.Trajectory See also -------- _to_topology """

        atom_list = [particle for particle in self.particles(show_ports)]

        top = self._to_topology(atom_list, chains, residues)

        # Coordinates.
        xyz = np.ndarray(shape=(1, top.n_atoms, 3), dtype='float')
        for idx, atom in enumerate(atom_list):
            xyz[0, idx] = atom.pos

        # Unitcell information.
        unitcell_angles = [90.0, 90.0, 90.0]
        if box is None:
            unitcell_lengths = np.empty(3)
            for dim, val in enumerate(self.periodicity):
                if val:
                    unitcell_lengths[dim] = val
                else:
                    unitcell_lengths[dim] = self.boundingbox.lengths[dim] + 0.5
        else:
            unitcell_lengths = box.lengths
            unitcell_angles = box.angles

        return md.Trajectory(xyz, top, unitcell_lengths=unitcell_lengths,
                             unitcell_angles=unitcell_angles)