@classmethod
def from_pair(cls, allow, deny):
    """Creates an overwrite from an allow/deny pair of :class:`Permissions`."""
    ret = cls()
    for key, value in allow:
        if value is True:
            setattr(ret, key, True)
    for key, value in deny:
        if value is True:
            setattr(ret, key, False)
    return ret
