code: def get_params(self, url):
          
          match = re.match(self.regex, url)
          if match is not None:
              params = match.groupdict()
              if not params:
                  params = {}
                  for i, group in enumerate(match.groups()[1:]):
                      params['_%s' % i] = group
              return params
          
          raise OEmbedException('No regex matched the url %s' % (url))
docs: Extract the named parameters from a url regex.  If the url regex does not contain
          named parameters, they will be keyed _0, _1, ...
          
          * Named parameters
          Regex:
          /photos/^(?P<year>\d{4})/(?P<month>\w{3})/(?P<day>\d{1,2})/(?P<object_id>\d+)/
          
          URL:
          http://www2.ljworld.com/photos/2009/oct/11/12345/
          
          Return Value:
          {u'day': '11', u'month': 'oct', u'object_id': '12345', u'year': '2009'}
          
          * Unnamed parameters
          Regex:
          /blah/([\w-]+)/(\d+)/
          
          URL:
          http://www.example.com/blah/hello/123/
          
          Return Value:
          {u'_0': 'hello', u'_1': '123'}