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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 _get_logical_raid_levels(self):
 """Gets the different raid levels configured on a server. :returns a dictionary of logical_raid_levels set to true. Example if raid level 1+0 and 6 are configured, it returns {'logical_raid_level_10': 'true', 'logical_raid_level_6': 'true'} """

        logical_drive_details = self._get_logical_drive_resource()
        raid_level = {}
        if logical_drive_details:
            for item in logical_drive_details:
                if 'Raid' in item:
                    raid_level_var = "logical_raid_level_" + item['Raid']
                    raid_level.update({raid_level_var: 'true'})
        return raid_level if len(raid_level.keys()) > 0 else None