docs: def read(url, **args):
      """Loads an object from a data URI."""
      info, data = url.path.split(',')
      info = data_re.search(info).groupdict()
      mediatype = info.setdefault('mediatype', 'text/plain;charset=US-ASCII')
      if ';' in mediatype:
          mimetype, params = mediatype.split(';', 1)
          params = [p.split('=') for p in params.split(';')]
          params = dict((k.strip(), v.strip()) for k, v in params)
      else:
          mimetype, params = mediatype, dict()
      data = base64.b64decode(data) if info['base64'] else urllib.unquote(data)
      return content_types.get(mimetype).parse(data, **params)