We currently have the following behavior:

sage: M = ModularFormsRing(Gamma0(2))
sage: E4 = ModularForms(1, 4).0
sage: F = M(E4)
sage: F[4].parent()
Modular Forms space of dimension 1 for Modular Group SL(2,Z) of weight 4 over Rational Field

The parent of F[4] is wrong as the group should be Gamma0(2).

CC: @videlec

Component: modular forms

Author: David Ayotte

Branch/Commit: ba35b10

Reviewer: Vincent Delecroix

Issue created by migration from https://trac.sagemath.org/ticket/34698