def loads(self, requirements_text):
        lines = re.findall(Requirement.spec_regex,
                           requirements_text,
                           re.MULTILINE)
        for line in lines:
            self.add(Requirement(line[0], "".join(line[1:])))
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,
            }