If I create function like this:
def mdl(input_shape):
model = Sequential()
model.add(Conv2D(depth=64, kernel_size=(3, 3), input_shape=input_shape, activation='relu'))
model.add(Dense(32), activation='relu')
model.add(Dropout(0.3))
model.add(Dense(32), activation='relu')
model.add(Dropout(0.3))
model.add(Dense(16), activation='relu')
model.add(Dropout(0.3))
model.add(Dense(1))
return model
and I care a lot about good programming practices, how should I indicate returning type of the function?