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_conflicting_initializers(self):
        class POINT(Structure):
            _fields_ = [("x", c_int), ("y", c_int)]
        # conflicting positional and keyword args
        self.assertRaises(TypeError, POINT, 2, 3, x=4)
        self.assertRaises(TypeError, POINT, 2, 3, y=4)

        # too many initializers
        self.assertRaises(TypeError, POINT, 2, 3, 4)