def predict_raw(model, periods):
    """Returns the raw output of a Prophet model.
    
    Paramaters
    ----------
    model : dict
        A trained Prophet model created with init_fit.
    periods : int
        The number of periods to forecast.
    cap : float
        An upper limit for the case of logistic growth.
    
    Returns
    -------
    prophet_output : DataFrame
        The output of m.predict() method of the Prophet class.
    """
    future = model['m'].make_future_dataframe(periods=periods)
    future['cap'] = model['cap']
    prophet_output = model['m'].predict(future)
    return prophet_output