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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 save_and_scan(filename, b64_data):
 """ Save `b64_data` to temporary file and scan it for viruses. Args: filename (str):
 Name of the file - used as basename for tmp file. b64_data (str):
 Content of the file encoded in base64. Returns: dict: ``{filename: ("FOUND", "virus type")}`` or blank dict. """

    with NTFile(suffix="_"+os.path.basename(filename), mode="wb") as ifile:
        ifile.write(
            b64decode(b64_data)
        )
        ifile.flush()

        os.chmod(ifile.name, 0755)

        return scan_file(ifile.name)