Access to Diode Parameters

Hello,

when working with pyspice 1.3 it was possible for me to change device parameters in thie way described below. With 1.4 this does not seem to work any more. Is there a new or alternate syntax?

#############################
import os
os.linesep="\n"

source=’’’
.title xxx

V1 N001 0 1 AC 1
D1 N001 0 john

.model john D (Is=4.352e-9 Rs=0 N=1.906)
.end

‘’’

parser = SpiceParser(source=source)
circuit = parser.build_circuit()

circuit.john._parameters[‘Is’] = 3e-08

simulator = circuit.simulator(temperature=25, nominal_temperature=25)
analysis = simulator.dc(V1=slice(0.1, 1,0.01))

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