a =  [1, 2, 3, 3, 3, 4, 5, 1, 1, 2, 4, 6, 7, 19]
b = 1
j = 1
#compare a[j] with everything less a[:b]
while (j < len(a)):
    isin = False
    for i in range(b):
            if (a[i] == a[j]):
                    isin = True
    if not isin:
            a[b] = a[j]
            b += 1
    j += 1

a = a[0:b]