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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 validate_ceph_pool_samples(self, samples, sample_type="resource pool"):
 """Validate ceph pool samples taken over time, such as pool object counts or pool kb used, before adding, after adding, and after deleting items which affect those pool attributes. The 2nd element is expected to be greater than the 1st; 3rd is expected to be less than the 2nd. :param samples: List containing 3 data samples :param sample_type: String for logging and usage context :returns: None if successful, Failure message otherwise """

        original, created, deleted = range(3)
        if samples[created] <= samples[original] or \
                samples[deleted] >= samples[created]:
            return ('Ceph {} samples ({}) '
                    'unexpected.'.format(sample_type, samples))
        else:
            self.log.debug('Ceph {} samples (OK): '
                           '{}'.format(sample_type, samples))
            return None