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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 aggregate(self, mapped_coll_generator, coll_type, visitor):
 """Hook called for each normalize.coll.Collection, after mapping over each of the items in the collection. The default implementation calls :py:meth:`normalize.coll.Collection.tuples_to_coll` with ``coerce=False``, which just re-assembles the collection into a native python collection type of the same type of the input collection. args: ``result_coll_generator=`` *generator func* Generator which returns (key, value) pairs (like :py:meth:`normalize.coll.Collection.itertuples`) ``coll_type=``\ *CollectionType* This is the :py:class:`normalize.coll.Collection`-derived *class* which is currently being reduced. ``visitor=``\ *Visitor* Context/options object """

        return coll_type.tuples_to_coll(mapped_coll_generator, coerce=False)