def override_plasticity_state(self, new_plasticity_state):
self._plasticity_setting_stack.append(self.plastic)<EOL>self.plastic=new_plasticity_state<EOL>
Temporarily disable plasticity of internal state.

This function should be implemented by all subclasses so that
after a call, the output should always be the same for any
given input pattern, and no call should have any effect that
persists after restore_plasticity_state() is called.

By default, simply saves a copy of the 'plastic' parameter to
an internal stack (so that it can be restored by
restore_plasticity_state()), and then sets the plastic
parameter to the given value (True or False).