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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 _merge_data(self, data: AnyMapping, *additional: AnyMapping) -> dict: r"""Merge base data and additional dicts. :param data: Base data. :param \*additional: Additional data dicts to be merged into base dict. """

        return defaults(
            dict(data) if not isinstance(data, dict) else data,
            *(dict(item) for item in additional))