Actually save the placeholder data into the Content object.

def save(self, page, language, data, change, extra_data=None):
        """Actually save the placeholder data into the Content object."""
        # if this placeholder is untranslated, we save everything
        # in the default language
        if self.untranslated:
            language = settings.PAGE_DEFAULT_LANGUAGE

        # the page is being changed
        if change:
            # we need create a new content if revision is enabled
            if(settings.PAGE_CONTENT_REVISION and self.name
                not in settings.PAGE_CONTENT_REVISION_EXCLUDE_LIST):
                Content.objects.create_content_if_changed(
                    page,
                    language,
                    self.name,
                    data
                )
            else:
                Content.objects.set_or_create_content(
                    page,
                    language,
                    self.name,
                    data
                )
        # the page is being added
        else:
            Content.objects.set_or_create_content(
                page,
                language,
                self.name,
                data
            )