def parse_attributes(attributes=None, classname=None):
if not attributes:<EOL><INDENT>attributes = {}<EOL><DEDENT>attributes.setdefault('<STR_LIT:class>', DEFAULT_CLASS_NAME)<EOL>if classname:<EOL><INDENT>attributes['<STR_LIT:class>'] = classname<EOL><DEDENT>return attributes<EOL>
Parses attributes,

    Args:
      attributes (dict): Input attributes.
      classname (:obj:`str`, optional): Class name of output SPAN tags.

    Returns:
      Parsed attributes. (dict)