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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 zone_update(cls, zone_id, records):
 """Update records for a zone"""

        cls.echo('Creating new zone file')
        new_version_id = Zone.new(zone_id)

        cls.echo('Updating zone records')
        cls.call('domain.zone.record.set', zone_id, new_version_id, records)

        cls.echo('Activation of new zone version')
        Zone.set(zone_id, new_version_id)

        return new_version_id