def mitjana_ph(nomf, epsilon):
    with open(nomf,'r') as f:
        l = []
        for linia in f:
            prod, mitjana = extreu_producte_mitjana(linia)
            if abs(mitjana - 7) < epsilon:
                l.append(prod)
    return l

def extreu_producte_mitjana(linia):
    lprod = linia.split(',')
    s = 0
    for mesura in lprod[1:]:
        s = s + float(mesura)
    m = s/(len(lprod)-1)
    return lprod[0], m