def load_installed_version(self):
        installed_packages = get_installed_pypackages()
        if self.package in installed_packages:
            self.version = "=={}".format(
                installed_packages[self.package].version)
def __init__(self, name: str, get_converter: t.Optional[t.Callable] = None) -> None:
        self.__name__ = name
        self.get_converter = get_converter