def __init__(self, groups=None):
        super(GroupedRequirements, self).__init__(NamedRequirements)
        self.groups = groups or self.default_groups
        self.filename = None
        self.create_default_groups()
def delete(id, env=None, headers=None):
        return request.send('post', request.uri_path("plans",id,"delete"), None, env, headers)