'Enables compression on lun.
:param lun: instance of VNXLun'

def enable_compression(self, lun):

    try:
        lun.enable_compression(ignore_thresholds=True)
    except storops_ex.VNXCompressionAlreadyEnabledError:
        LOG.warning('Compression    has    already    been    enabled    on    %s.', lun.name)
