Add missing include when generatin jacobian_apply, but not jacobian

python/dune/perftool/pdelab/localoperator.py

@@ -861,6 +861,7 @@ def generate_jacobian_kernels(form, original_form):
         with global_context(form_type="jacobian_apply"):
             for measure in set(i.integral_type() for i in jac_apply_form.integrals()):
                 with global_context(integral_type=measure):
+                    from dune.perftool.pdelab.signatures import assembler_routine_name
                     with global_context(kernel=assembler_routine_name()):
                         kernel = [k for k in get_backend(interface="generate_kernels_per_integral")(jac_apply_form.integrals_by_type(measure))]
                 operator_kernels[(measure, 'jacobian_apply')] = kernel