def avg_score(qual):
    """Return AVG score of a Fastq sequence

    Parametres
    ----------
    qual : str
        string contain the quality of the sequence encode in Phred

    Returns
    -------
    float
        Average quality of the sequences

    """
    # Translate the Quality to numbers
    avgQual = [ord(c)-33 for c in qual.rstrip("\n")]

    return avgQual