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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 __build_export(self, stats):
 """Build the export lists."""

        export_names = []
        export_values = []

        if isinstance(stats, dict):
            # Stats is a dict
            # Is there a key ?
            if 'key' in iterkeys(stats) and stats['key'] in iterkeys(stats):
                pre_key = '{}.'.format(stats[stats['key']])
            else:
                pre_key = ''
            # Walk through the dict
            for key, value in iteritems(stats):
                if isinstance(value, bool):
                    value = json.dumps(value)
                if isinstance(value, list):
                    try:
                        value = value[0]
                    except IndexError:
                        value = ''
                if isinstance(value, dict):
                    item_names, item_values = self.__build_export(value)
                    item_names = [pre_key + key.lower() + str(i) for i in item_names]
                    export_names += item_names
                    export_values += item_values
                else:
                    export_names.append(pre_key + key.lower())
                    export_values.append(value)
        elif isinstance(stats, list):
            # Stats is a list (of dict)
            # Recursive loop through the list
            for item in stats:
                item_names, item_values = self.__build_export(item)
                export_names += item_names
                export_values += item_values
        return export_names, export_values