Most likely that means there is something wrong on the previous line. E.g. that you forgot to terminate it with a comma. That is not necessary in python in general, but you are defining a list of functions here. That is how the Sequential API works.
They don’t give us much guidance on the Sequential and Functional APIs here and the documentation is pretty rough going as well. Here is a thread from ai_curious which is probably the best way to get a handle on how to use these two Keras APIs.