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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 physical_drives(self):
 """Gets the resource HPEPhysicalDriveCollection of ArrayControllers"""

        return physical_drive.HPEPhysicalDriveCollection(
            self._conn, utils.get_subresource_path_by(
                self, ['Links', 'PhysicalDrives']),
            redfish_version=self.redfish_version)