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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 _format_contents(self, prefix, separator, suffix):
 """Format the parameters. The formatting is done using the three arguments suplied to this function. Arguments --------- prefix: str separator: str suffix: str Returns ------- str """


        params = self._list_args_kwargs()

        if len(params) <= 0:
            return ''

        string = prefix + dumps_list(params, escape=self.escape,
                                     token=separator) + suffix

        return string