def _process_output_options(self):
        if not self.args.output_options:
            self.args.output_options = (
                OUTPUT_OPTIONS_DEFAULT
                if self.env.stdout_isatty
                else OUTPUT_OPTIONS_DEFAULT_STDOUT_REDIRECTED
            )

        unknown_output_options = set(self.args.output_options) - OUTPUT_OPTIONS
        if unknown_output_options:
            self.error(
                'Unknown output options: %s' % ','.join(unknown_output_options)
            )

        if self.args.download and OUT_RESP_BODY in self.args.output_options:
            # Response body is always downloaded with --download and it goes
            # through a different routine, so we remove it.
            self.args.output_options = str(
                set(self.args.output_options) - set(OUT_RESP_BODY))
Apply defaults to output options, or validate the provided ones.
dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/httpie/input.py/Parser._process_output_options