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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_field(self, state, field_name, field_type):
 """ Gets the value of an instance field. """

        # get field reference
        field_ref = SimSootValue_InstanceFieldRef.get_ref(state=state,
                                                          obj_alloc_id=self.heap_alloc_id,
                                                          field_class_name=self.type,
                                                          field_name=field_name,
                                                          field_type=field_type)
        # load value from java memory
        return state.memory.load(field_ref, none_if_missing=True)