for

for i in range(3):
    print(i)

1
2
3

for i in range(3):
    print(i)
else:
    print('no left')

0
1
2
no left

Skip some step

# don't contain 5 (way 1)
for i in [x for x in range(10) if x != 5]:
    print i

# don't contain 5 (way 2)
for i in list(range(5)) + list(range(6, 10)):
    print i

# next (skip 5)
xr = iter(range(10))
for i in xr:
    print(i)
    if i == 4: next(xr)

# continue (skip 5)
for i in range(10):
    if i == 5: continue
    print(i)

while

i = 1
while i < 4:
    print(i)
    i += 1

1
2
3

You can also use next and continue like in the case of for but with caution!

break

for i in range(6):
    print(i)
    if i==2: break

0
1
2

i = 1
while i < 6:
    print(i)
    if i==3: break
    i += 1

1
2
3