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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 _write_to_error(self, s, truncate=False):
 """Writes the given output to the error file, appending unless `truncate` is True."""

        # if truncate is True, set write mode to truncate
        with open(self._errorfile, 'w' if truncate else 'a') as fp:
            fp.writelines((to_text(s)), )