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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 _create_import_log(items):
 """ Used to create log with successfully imported data. """

    log = []

    for item in items:
        if isinstance(item, MetadataFile):
            log.append(
                "Metadata file '%s' successfully imported." % item.filename
            )
        elif isinstance(item, EbookFile):
            log.append(
                "Ebook file '%s' successfully imported." % item.filename
            )
        elif isinstance(item, DataPair):
            meta = item.metadata_file.filename
            data = item.ebook_file.filename
            log.extend([
                "Metadata and data files paired to epub. import request:",
                "\tMetadata file '%s' successfully imported." % meta,
                "\tEbook file '%s' successfully imported." % data
            ])

    return log