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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 form_invalid(self, form, forms, open_tabs, position_form_default):
 """ Called if a form is invalid. Re-renders the context data with the data-filled forms and errors. """

        # return self.render_to_response( self.get_context_data( form = form, forms = forms ) )
        return self.render_to_response(self.get_context_data(form=form, forms=forms, open_tabs=open_tabs, position_form_default=position_form_default))