@register.tag('experiment')
def experiment(parser, token):
    try:
        token_contents = token.split_contents()
        experiment_name, alternative, weight, user_variable = _parse_token_contents(token_contents)

        node_list = parser.parse(('endexperiment', ))
        parser.delete_first_token()
    except ValueError:
        raise template.TemplateSyntaxError("Syntax should be like :"
                "{% experiment experiment_name alternative [weight=val] [user=val] %}")

    return ExperimentNode(node_list, experiment_name, alternative, weight, user_variable)
Split Testing experiment tag has the following syntax :
dataset/ETHPy150Open mixcloud/django-experiments/experiments/templatetags/experiments.py/experiment