Define a modular form from its q-expansion coefficients
I have a certain modular form for Γ(N) and weight 0 which I know but just by it's q-expansion coefficients, and I want to compute the action of Hecke operators on this modular form. How do I define a modular form object from its q-expansion coefficients, so that I can use it as an input for M.hecke_operator?
Please give us the N and the first coefficients. Else there is hard to give a pointed answer.