def verify_request(self, oauth_request):
        """Verifies an api call and checks all the parameters."""
        # -> consumer and token
        version = self._get_version(oauth_request)
        consumer = self._get_consumer(oauth_request)
        # Get the access token.
        token = self._get_token(oauth_request, 'access')
        self._check_signature(oauth_request, consumer, token)
        parameters = oauth_request.get_nonoauth_parameters()
        return consumer, token, parameters
Verifies an api call and checks all the parameters.
twitter/oauth.py