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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def follow_all_url(parser, token):
 """ Renders the URL to follow an object as both actor and target :: <a href="{% follow_all_url other_user %}"> {% if request.user|is_following:other_user %} stop following {% else %} follow {% endif %} </a> <a href="{% follow_all_url other_user 'watching' %}"> {% is_following user group "watching" as is_watching %} {% if is_watching %} stop watching {% else %} watch {% endif %} </a> """

    bits = token.split_contents()
    if len(bits) > 3:
        raise TemplateSyntaxError(
            "Accepted format {% follow_all_url [instance] %} or {% follow_url [instance] [flag] %}"
        )
    elif len(bits) == 2:
        return DisplayActivityFollowUrl(bits[1], actor_only=False)
    else:
        flag = bits[2][1:-1]
        return DisplayActivityFollowUrl(bits[1], actor_only=False, flag=flag)