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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 _err(self, errclass: str="error", *args) -> "Err": """ Creates an error """

        error = self._new_err(errclass, *args)
        if self.log_errs is True:
            sep = " "
            if self.log_format == "csv":
                sep = ","
            msg = str(datetime.now()) + sep + \
                self._errmsg(error, msgformat=self.log_format)
            self.logger.error(msg)
        print(self._errmsg(error))
        self._add(error)
        return error