Save images of dose-response curve-fits for each model.

        Parameters
        ----------
        directory : str
            Directory where the PNG files will be saved.
        format : str, optional
            Image output format. Valid options include: png, pdf, svg, ps, eps
        recommended_only : bool, optional
            If True, only recommended models for each session are included. If
            no model is recommended, then a row with it's ID will be included,
            but all fields will be null.

        Returns
        -------
        None

def save_plots(self, directory, format="png", recommended_only=False):
        """
        Save images of dose-response curve-fits for each model.

        Parameters
        ----------
        directory : str
            Directory where the PNG files will be saved.
        format : str, optional
            Image output format. Valid options include: png, pdf, svg, ps, eps
        recommended_only : bool, optional
            If True, only recommended models for each session are included. If
            no model is recommended, then a row with it's ID will be included,
            but all fields will be null.

        Returns
        -------
        None

        """
        for i, session in enumerate(self):
            session.save_plots(
                directory, prefix=str(i), format=format, recommended_only=recommended_only
            )