Looks like setting the concurrency isn't allowed in `create_function` or `update_function_configuration` This would require callouts to two separate functions: [put_function_concurrency](http://boto3.readthedocs.io/en/latest/reference/services/lambda.html#Lambda.Client.put_function_concurrency) [delete_function_concurrency](http://boto3.readthedocs.io/en/latest/reference/services/lambda.html#Lambda.Client.delete_function_concurrency)