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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def with_labels(self, selectable, base=None, **mapper_args):
 """Map a selectable directly, wrapping the selectable in a subquery with labels. The class and its mapping are not cached and will be discarded once dereferenced (as of 0.6.6). :param selectable: an :func:`.expression.select` construct. :param base: a Python class which will be used as the base for the mapped class. If ``None``, the "base" argument specified by this :class:`.SQLSoup` instance's constructor will be used, which defaults to ``object``. :param mapper_args: Dictionary of arguments which will be passed directly to :func:`.orm.mapper`. """


        # TODO give meaningful aliases
        return self.map(
                    expression._clause_element_as_expr(selectable).
                            select(use_labels=True).
                            alias('foo'), base=base, **mapper_args)