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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 set_field_value(self, field_name, value):
 """ Set value of request field named `field_name`. Use this method to apply changes to object which is affected by request. Values are set on `view._json_params` dict. If `field_name` is not affected by request, it is added to `self.fields` which makes field processors which are connected to `field_name` to be triggered, if they are run after this method call(connected to events after handler that performs method call). :param field_name: Name of request field value of which should be set. :param value: Value to be set. """

        self.view._json_params[field_name] = value
        if field_name in self.fields:
            self.fields[field_name].new_value = value
            return

        fields = FieldData.from_dict({field_name: value}, self.model)
        self.fields.update(fields)