Export particle and datetime data to Pickled objects.
            This can be used to debug or to generate different output
            in the future.

def export(cls, folder, particles, datetimes):
        """
            Export particle and datetime data to Pickled objects.
            This can be used to debug or to generate different output
            in the future.
        """
        if not os.path.exists(folder):
            os.makedirs(folder)

        particle_path = os.path.join(folder, 'particles.pickle')
        f = open(particle_path, "wb")
        pickle.dump(particles, f)
        f.close()

        datetimes_path = os.path.join(folder, 'datetimes.pickle')
        f = open(datetimes_path, "wb")
        pickle.dump(datetimes, f)
        f.close()