def load_pip_requirements(self, files_map=None, freeze=True):
        if files_map is None:
            files_map = self.default_pip_files
        for group, requirements_txt in files_map.items():
            path = Path(requirements_txt)
            if not path.exists() and group.lower() == "all" and freeze:
                cmd = envoy.run("pip freeze")
                self[group].loads(cmd.std_out)
            elif path.exists():
                self[group].load(path)
def __init__(self, saddr, gaddr, glen):
        self.saddr = saddr
        self.gaddr = gaddr
        self.glen = glen
        if ip_address(self.saddr).version != \
           ip_address(self.gaddr).version:
            raise ValueError('Source and group addresses must be of the '
                             'same address family.')