How to save and retrieve trained ai locally from python backend

I am trying to store a hugging face transformer ai model for each individual user locally instead of storing it in a database.

model = BertForSequenceClassification.from_pretrained('bert-base-uncased',num_labels=2)
model.save_pretrained("locallystored")

I then would like to train that users model that I stored locally. I send a websocket to backend to train the model stored in the users local machine.

socketio.on("willtraintheusersmodel")
    model = BertForSequenceClassification.from_pretrained('locallystored')
    *training*
    model.train() 
    model.save_pretrained("locallystored")
    #then I update the changes made

How can I save a model in the users computer locally and retrieve it anytime i need to train or make predictions? I am trying to make this work in production with multiple users.

I have a python-socketio backend with react frontend

Any help would be extremely appreciated thanks.