Prints task information.

            `env`
                Runtime ``Environment`` instance.
            `args`
                Arguments object from arg parser.

def execute(self, env, args):
        """ Prints task information.

            `env`
                Runtime ``Environment`` instance.
            `args`
                Arguments object from arg parser.
            """

        task_name = args.task_name

        if task_name is None:
            if not env.task.active:
                raise errors.NoActiveTask
            task_name = env.task.name

        tasks = env.task.get_list_info(task_name)
        if not tasks:
            raise errors.TaskNotFound(task_name)

        _print_tasks(env, tasks)