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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 add_field_processors(config, processors, model, field):
 """ Add processors for model field. Under the hood, regular nefertari event subscribed is created which calls field processors in order passed to this function. Processors are passed following params: * **new_value**: New value of of field. * **instance**: Instance affected by request. Is None when set of items is updated in bulk and when item is created. * **field**: Instance of nefertari.utils.data.FieldData instance containing data of changed field. * **request**: Current Pyramid Request instance. * **model**: Model class affected by request. * **event**: Underlying event object. Each processor must return processed value which is passed to next processor. :param config: Pyramid Congurator instance. :param processors: Sequence of processor functions. :param model: Model class for field if which processors are registered. :param field: Field name for which processors are registered. """

    before_change_events = (
        BeforeCreate,
        BeforeUpdate,
        BeforeReplace,
        BeforeUpdateMany,
        BeforeRegister,
    )

    def wrapper(event, _processors=processors, _field=field):
        proc_kw = {
            'new_value': event.field.new_value,
            'instance': event.instance,
            'field': event.field,
            'request': event.view.request,
            'model': event.model,
            'event': event,
        }
        for proc_func in _processors:
            proc_kw['new_value'] = proc_func(**proc_kw)

        event.field.new_value = proc_kw['new_value']
        event.set_field_value(_field, proc_kw['new_value'])

    for evt in before_change_events:
        config.add_subscriber(wrapper, evt, model=model, field=field)