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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 nullify_offsets(offsets):
 """Modify offsets metadata so that the partition offsets have null payloads. :param offsets: dict {<topic>: {<partition>: <offset>}} :returns: a dict topic: partition: offset """

    result = {}
    for topic, partition_offsets in six.iteritems(offsets):
        result[topic] = _nullify_partition_offsets(partition_offsets)
    return result