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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 _parse_api_options(self, options, query_string=False):
 """Select API options out of the provided options object. Selects API string options out of the provided options object and formats for either request body (default) or query string. """

        api_options = self._select_options(options, self.API_OPTIONS)
        if query_string:
            # Prefix all options with "opt_"
            query_api_options = {}
            for key in api_options:
                # Transform list/tuples into comma separated list
                if isinstance(api_options[key], (list, tuple)):
                    query_api_options[
                        'opt_' + key] = ','.join(api_options[key])
                else:
                    query_api_options[
                        'opt_' + key] = api_options[key]
            return query_api_options
        else:
            return api_options