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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 partition(self, mapped_values):
 """Organize the mapped values by their key. Returns an unsorted sequence of tuples with a key and a sequence of values. """

        partitioned_data = collections.defaultdict(list)
        for key, value in mapped_values:
            partitioned_data[key].append(value)
        return partitioned_data.items()