Calling Framework7 function

Morning and a happy new year.

I am trying to call Framework7 functions via JS .

When I try and do a call like app.f7function I get not a not found error.

Cannot read property 'create' of undefined

If I try and include an app.js file for F7 it says Framework7 already defined.

What is it defined as? how do I call F7 functions?

Thanks