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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 perturbed_trajectory(trajectory, sensitivity_trajectory, delta=1e-4):
 """ Slightly perturb trajectory wrt the parameter specified in sensitivity_trajectory. :param trajectory: the actual trajectory for an ODE term :type trajectory: :class:`Trajectory` :param sensitivity_trajectory: sensitivity trajectory (dy/dpi for all timepoints t) :type sensitivity_trajectory: :class:`Trajectory` :param delta: the perturbation size :type delta: float :return: :class:`Trajectory` """

    sensitivity_trajectory_description = sensitivity_trajectory.description
    assert(isinstance(sensitivity_trajectory_description, SensitivityTerm))
    assert(np.equal(trajectory.timepoints, sensitivity_trajectory.timepoints).all())

    return Trajectory(trajectory.timepoints,
                      trajectory.values + sensitivity_trajectory.values * delta,
                      PerturbedTerm(sensitivity_trajectory_description.ode_term,
                                    sensitivity_trajectory_description.parameter,
                                    delta))