__init__.py 文件源码

def _dep_map(self):
        try:
            return self.__dep_map
        except AttributeError:
            dm = self.__dep_map = {None: []}
            for name in 'requires.txt', 'depends.txt':
                for extra, reqs in split_sections(self._get_metadata(name)):
                    if extra:
                        if ':' in extra:
                            extra, marker = extra.split(':', 1)
                            if invalid_marker(marker):
                                # XXX warn
                                reqs = []
                            elif not evaluate_marker(marker):
                                reqs = []
                        extra = safe_extra(extra) or None
                    dm.setdefault(extra, []).extend(parse_requirements(reqs))
            return dm