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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 output(self, context, *args, **kwargs):
 """ Allow all readers to use eventually use output_fields XOR output_type options. """


        output_fields = self.output_fields
        output_type = self.output_type

        if output_fields and output_type:
            raise UnrecoverableError("Cannot specify both output_fields and output_type option.")

        if self.output_type:
            context.set_output_type(self.output_type)

        if self.output_fields:
            context.set_output_fields(self.output_fields)

        yield