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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 zero_disk(self, disk_xml=None):
 """ Collector and publish not zeroed disk metrics """


        troubled_disks = 0
        for filer_disk in disk_xml:
            raid_state = filer_disk.find('raid-state').text
            if not raid_state == 'spare':
                continue
            is_zeroed = filer_disk.find('is-zeroed').text

            if is_zeroed == 'false':
                troubled_disks += 1
        self.push('not_zeroed', 'disk', troubled_disks)