def get_peptide_quant(quantdata, quanttype):
    """Parses lists of quantdata and returns maxvalue from them. Strips NA"""
    parsefnx = {'precur': max}
    quantfloats = []
    for q in quantdata:
        try:
            quantfloats.append(float(q))
        except (TypeError, ValueError):
            pass
    if not quantfloats:
        return 'NA'
    return str(parsefnx[quanttype](quantfloats))
