def METHOD_NAME(self, files, spine, guide):
    """Create a dictionary with all metadata for the content.opf
    file properly escaped.
    """
    metadata = super(Epub3Builder, self).METHOD_NAME(
        files, spine, guide)
    metadata['description'] = self.esc(self.config.epub3_description)
    metadata['contributor'] = self.esc(self.config.epub3_contributor)
    metadata['page_progression_direction'] = self.esc(
        self.config.epub3_page_progression_direction) or 'default'
    return metadata