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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:
 preferred_combiner: Callable=replace_combiner, """Marks a ``Callable`` as the producer of a named value. Parameters value_name : The name of the new dynamic value pipeline. source : A callable source for the dynamic value pipeline. preferred_combiner : A strategy for combining the source and the results of any calls to mutators in the pipeline. ``vivarium`` provides the strategies ``replace_combiner`` (the default), ``list_combiner``, and ``set_combiner`` which are importable from ``vivarium.framework.values``. Client code may define additional strategies as necessary. preferred_post_processor : A strategy for processing the final output of the pipeline. ``vivarium`` provides the strategies ``rescale_post_processor`` and ``joint_value_post_processor`` which are importable from ``vivarium.framework.values``. Client code may define additional strategies as necessary. Returns ------- Callable A callable reference to the named dynamic value pipeline. """

        return self._value_manager.register_value_producer(value_name, source,
                                                           preferred_combiner,
                                                           preferred_post_processor)