def load(self, filename, create_if_missing=True):
        filename = Path(filename)
        if not filename.exists() and create_if_missing:
            self.load_pip_requirements()
            with filename.open("w") as f:
                f.write(yaml.dump(self.serialized, default_flow_style=False,
                                  encoding=None))
            self.filename = filename
            return self.save(filename)
        with filename.open() as f:
            for group, requirements in yaml.load(f.read()).items():
                for requirement in requirements:
                    self[group].add(Requirement.coerce(requirement))
        self.filename = filename
def _match_less_than_or_equal(search_base, attribute, value, candidates):
        matches = list()
        for entry in candidates:
            dn = entry.get("dn")
            if not dn.endswith(search_base):
                continue

            value_from_directory = entry.get("attributes").get(attribute)
            if str(value_from_directory) <= str(value):
                entry["type"] = "searchResEntry"
                matches.append(entry)

        return matches