def coerce(cls, string):
        """Create a :class:`Requirement` object from a given package spec."""
        match = re.match(cls.spec_regex, string)
        if not match:
            raise InvalidRequirementSpecError("could not parse requirement")
        package = match.group(1)
        if all(match.group(2, 3)):
            version = "".join(match.group(2, 3))
        else:
            version = None
        return cls(package, version)
def lazy_gettext(self, text: str, lang: str = None):
        if not babel_imported:
            raise RuntimeError('babel module is not imported. Check that you installed it.')
        return LazyProxy(self.gettext, text, lang, enable_cache=False)