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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 best_fts_version():
    "Discovers the most advanced supported SQLite FTS version"
    conn = sqlite3.connect(":memory:")
    for fts in ("FTS5", "FTS4", "FTS3"):
        try:
            conn.execute("CREATE VIRTUAL TABLE v USING {} (t TEXT);".format(fts))
            return fts
        except sqlite3.OperationalError:
            continue
    return None