I now separates between MyFig and MyFig_base. MyFig_base can be used by overwritting the __init__ function and the plot function, very much like in v1.0.0, you just don't need update, remark the axes should be created in __init__ not in plot. The MyFig class however is smarter, and the user just need to overwrite defineKeywords and addAxes, yes, you don't need __init__! as their names suggests in defineKeywords you should update self.keywords, in addAxes you should add the objects MyAxes. Now the figure object reads a tuple of data object as argument (not optional anymore) each index for the axes. This behaviour can be overwritten in the function MyFig::formatRawdata, and MyFig::set_rawdata. Remark now the MyFig_base keywords became attributes: self.keywords['fignum'] -> self.fignum...