use_secrets.py

import os
from urllib.request import urlopen
import streamlit as st
from keras_model import model # your custom model

my_email = st.secrets['email']
model_weight_file = st.secrets['model_url']

if not os.path.exists('./best_weights.h5'):
    u = urlopen(model_weight_file)
    data = u.read()
    u.close()
    with open('best_weights.h5', 'wb') as f:
        f.write(data)

...
model = model.load_weights('best_weights.h5')
...
st.write(f'My email is {my_email}')