def diff(other, match=None, clean=False):
    """Find differences between this manifest and another.

        This manifest is compared to ``other``.

        If ``match`` is provided, the two manifests are filtered against this
        matcher and only entries satisfying the matcher are compared.

        If ``clean`` is True, unchanged files are included in the returned
        object.

        Returns a dict with paths as keys and values of 2-tuples of 2-tuples of
        the form ``((node1, flag1), (node2, flag2))`` where ``(node1, flag1)``
        represents the node and flags for this manifest and ``(node2, flag2)``
        are the same for the other manifest.
        """
