Simply duplicating the following signatures from Assembler with
ufc::form instead of Form in PyDolfin would be nice:
assemble(self, Form form) -> real
assemble(self, Form form, SubDomain sub_domain) -> real
assemble(self, Form form,
dolfin::MeshFunction<(dolfin::uint)> cell_domains,
dolfin::MeshFunction<(dolfin::uint)> exterior_facet_domains,
dolfin::MeshFunction<(dolfin::uint)> interior_facet_domains) -> real
assemble(self, GenericTensor A, Form form, bool reset_tensor=True)
assemble(self, GenericTensor A, Form form, SubDomain
sub_domain, bool reset_tensor=True)