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 read_current_from_device(self):
        collection = self.client.api.cm.shared.licensing.pools_s.get_collection(
            requests_params=dict(
                params="$filter=name+eq+'{0}'".format(self.want.name)
            )
        )
        resource = collection.pop()
        result = resource.attrs
        return Parameters(result)