This one's tricky...check for equality,
        then for contains.

def handle_literal(self, val, checkable):
        '''This one's tricky...check for equality,
        then for contains.
        '''
        # I.e., spec: {'x': 1}, data: {'x': 1}
        if val == checkable:
            yield True
            return
        # I.e., spec: {'x': 1}, data: {'x': [1, 2, 3]}
        else:
            try:
                yield val in checkable
                return
            except TypeError:
                pass
        yield False