Slicing a list using a variable, in Python

Why does it have to be a single variable? Just use two variables:

i, j = 2, 4
a[i:j]

If it really needs to be a single variable you could use a tuple.

With the assignments below you are still using the same type of slicing operations you show, but now with variables for the values.

a = range(10)
i = 2
j = 4

then

print a[i:j]
[2, 3]

that's what slice() is for:

a = range(10)
s = slice(2,4)
print a[s]

That's the same as using a[2:4].