l  = [1,1,1,2,2,2,2,3,3,3,4,4,5,5,5]
l_u, l_u2 = set(l), []
print(l_u2)

#///////////////////////

i = 0
l_u2.append(l[i])
for x in range(0, len(l)-1):
    if l[i] != l[i+1]:
        l_u2.append(l[i+1])
    i = i + 1
print(l_u2)