example of the simulator code structure

sim.py

def simulator(initial_state, parameter):
	state = initial_state
	for t in range(timesteps):
		state = next_state(state,parameter)
		print(state)


#############################################
# but I need to be able to do something like

parameter = 0
state = 0

for t in range(timesteps):
	state = initialise_simulator(state, initial_parameter)
	parameter = update_parameter(state, parameter)