code: def get_epub_opf_xml(filepath):
      '''
      Returns the file.OPF contents of the ePub file
      '''
      if not zipfile.is_zipfile(filepath):
          raise EPubException('Unknown file')
  
      # print('Reading ePub file: {}'.format(filepath))
      zf = zipfile.ZipFile(filepath, 'r', compression=zipfile.ZIP_DEFLATED, allowZip64=True)
      container = zf.read('META-INF/container.xml')
      container_xmldoc = minidom.parseString(container)
      # e.g.: <rootfile full-path="content.opf" media-type="application/oebps-package+xml"/>
      opf_filepath = container_xmldoc.getElementsByTagName('rootfile')[0].attributes['full-path'].value
      return zf.read(opf_filepathf get_epub_opf_xml(filepath):
      '''
      Returns the file.OPF contents of the ePub file
      '''
      if not zipfile.is_zipfile(filepath):
          raise EPubException('Unknown file')
  
      # print('Reading ePub file: {}'.format(filepath))
      zf = zipfile.ZipFile(filepath, 'r', compression=zipfile.ZIP_DEFLATED, allowZip64=True)
      container = zf.read('META-INF/container.xml')
      container_xmldoc = minidom.parseString(container)
      # e.g.: <rootfile full-path="content.opf" media-type="application/oebps-package+xml"/>
      opf_filepath = container_xmldoc.getElementsByTagName('rootfile')[0].attributes['full-path'].value
      return zf.read(opf_filepath)
docs: Returns the file.OPF contents of the ePub file