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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 cursor():
 """Database cursor generator. Commit on context exit."""

    try:
        cur = conn.cursor()
        yield cur
    except (db.Error, Exception) as e:
        cur.close()
        if conn:
            conn.rollback()
        print(e.message)
        raise
    else:
        conn.commit()
        cur.close()