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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 fw_retry_failures_delete(self):
 """This routine is called for retrying the delete cases. """

        for tenant_id in self.fwid_attr:
            try:
                with self.fwid_attr[tenant_id].mutex_lock:
                    # For both create and delete case
                    fw_data = self.get_fw_by_tenant_id(tenant_id)
                    if fw_data is None:
                        LOG.info("No FW for tenant %s", tenant_id)
                        continue
                    result = fw_data.get('result').split('(')[0]
                    if result == fw_constants.RESULT_FW_DELETE_INIT:
                        fw_dict = self.fwid_attr[tenant_id].get_fw_dict()
                        # This means a restart has happened before the FW is
                        # completely deleted
                        if not fw_dict:
                            # Need to fill fw_dict from fw_data
                            fw_dict = self.fill_fw_dict_from_db(fw_data)
                        self.retry_failure_fab_dev_delete(tenant_id, fw_data,
                                                          fw_dict)
            except Exception as exc:
                LOG.error("Exception in retry failure delete %s",
                          str(exc))