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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 _get_checksum():
 """ Get the checksum of the RPM Database. Returns: hexdigest """

    digest = hashlib.sha256()
    with open(RPM_PATH, "rb") as rpm_db_fh:
        while True:
            buff = rpm_db_fh.read(0x1000)
            if not buff:
                break
            digest.update(buff)
    return digest.hexdigest()