def groups_option(f):
    new_func = click.option("-g", "--groups",
                            help="Comma-separated list of requirement groups "
                            "to include.")(f)
    return update_wrapper(new_func, f)
def __init__(self, directory=None):
        if directory is None:
                directory = []
        import copy
        self.directory = copy.deepcopy(directory)
        self.bound = False
        self.start_tls_called = False
        self.extend = self.Extend(self)

        self.operation = {
                    "!" : self._search_not,
                    "&" : self._search_and,
                    "|" : self._search_or,
            }