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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 is_gff_db(db_fname):
 """ Return True if the given filename is a GFF database. For now, rely on .db extension. """

    if not os.path.isfile(db_fname):
        return False
    if db_fname.endswith(".db"):
        return True
    return False