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 test_can_encode_relationship_with_alternative_names(self):
        a = Node("Person", nom=u"Aimée")
        b = Node("Person", nom=u"Baptiste")
        ab = KNOWS_FR(a, b)
        encoded = cypher_repr(ab, related_node_template=u"{property.nom}")
        self.assertEqual(u"(Aimée)-[:CONNAÎT {}]->(Baptiste)", encoded)