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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 _from_rest_on_update(model, props):
 """ Assign the default values when updating a model This is done on fields with `on_update=<value>`. """


    fields = model.get_fields_with_prop('on_update')

    for field in fields:
        props[field[0]] = field[1]