l=[]
for _ in range(8):
tmp=('0b'+(_*'1').ljust(8,'0'))
tmp=int(tmp,2)
l.append(tmp)
print(l)
#[0, 128, 192, 224, 240, 248, 252, 254]

l=[]
for _ in range(8):
tmp=('0b'+(_*'1').ljust(8,'0'))
tmp=int(tmp,2)
l.append(tmp)
print(l)
#[0, 128, 192, 224, 240, 248, 252, 254]