'Processes a request_token request and returns the
request token on success.'

def fetch_request_token(self, oauth_request):

    try:
        token = self._get_token(oauth_request, 'request')
    except OAuthError:
        version = self._get_version(oauth_request)
        consumer = self._get_consumer(oauth_request)
        self._check_signature(oauth_request, consumer, None)
        token = self.data_store.fetch_request_token(consumer)
    return token
