modular_form() hangs in sage 9.5 but works in older sage version

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Note that the conductor is rather large :

sage: E.conductor()
283312

This seems to hang inside

ModularSymbols(283312, sign=1, base_ring=QQ)

This hangs when trying to compute the rank

src/sage/modular/modsym/ambient.py(188)__init__()
186             formula = None
187 
188         rank = self.rank()