code: def _clear_policy(self, lambda_name):
          
          try:
              policy_response = self.lambda_client.get_policy(
                  FunctionName=lambda_name
              )
              if policy_response['ResponseMetadata']['HTTPStatusCode'] == 200:
                  statement = json.loads(policy_response['Policy'])['Statement']
                  for s in statement:
                      delete_response = self.lambda_client.remove_permission(
                          FunctionName=lambda_name,
                          StatementId=s['Sid']
                      )
                      if delete_response['ResponseMetadata']['HTTPStatusCode'] != 204:
                          logger.error('Failed to delete an obsolete policy statement: {}'.format(policy_response))
              else:
                  logger.debug('Failed to load Lambda function policy: {}'.format(policy_response))
          except ClientError as e:
              if e.args[0].find('ResourceNotFoundException') > -1:
                  logger.debug('No policy found, must be first run.')
              else:
                  logger.error('Unexpected client error {}'.format(e.args[0]))
docs: Remove obsolete policy statements to prevent policy from bloating over the limit after repeated updates.