AttributeError: 'str' object has no attribute 'save_weights'

[otuns]

ce_interval': (0.9805931206541726, 0.9853281119637217)}}
hp_search_1 | Saving model parameters to output file /logs/modelsnewdat_model_selu_0.json95c19ae5-da1b-4a76-9ef2-965222ceb869.h5
deepsurv__1 | Traceback (most recent call last):
deepsurv__1 | File "/deepsurv_run.py", line 165, in
deepsurv__1 | save_model(model, output_file)
deepsurv__1 | File "/deepsurv_run.py", line 100, in save_model
deepsurv__1 | model.save_weights(output_file)
deepsurv__1 | AttributeError: 'str' object has no attribute 'save_weights'
deepsurv_1 exited with code 1

Please, why am I getting this error?