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 testDeviceWrapper(self):
    wrapper_type = rnn_cell_wrapper_v2.DeviceWrapper
    x = array_ops.zeros([1, 3])
    m = array_ops.zeros([1, 3])
    cell = rnn_cell_impl.GRUCell(3)
    wrapped_cell = wrapper_type(cell, "/cpu:0")
    children = wrapped_cell._trackable_children()
    wrapped_cell.get_config()  # Should not throw an error
    self.assertIn("cell", children)
    self.assertIs(children["cell"], cell)

    outputs, _ = wrapped_cell(x, m)
    self.assertIn("cpu:0", outputs.device.lower())