[Python] Is there a need for range(len(a))?

One frequently finds expressions of this type in python questions on SO. Either for just accessing all items of the iterable

for i in range(len(a)):
print(a)


Which is just a clumbersome way of writing:

for e in a:
print(e)


Or for assigning to elements of the iterable:

for i in range(len(a)):
a = a * 2


Which should be the same as:

for i, e in enumerate(a):
a = e * 2
# Or if it isn't too expensive to create a new iterable
a = [e * 2 for e in a]


Or for filtering over the indices:

for i in range(len(a)):
if i % 2 == 1: continue
print(a)


Which could be expressed like this:

for e in a [::2]:
print(e)


Or when you just need the length of the list, and not its content:

for _ in range(len(a)):
doSomethingUnrelatedToA()


Which could be:

for _ in a:
doSomethingUnrelatedToA()


In python we have enumerate, slicing, filter, sorted, etc... As python for constructs are intended to iterate over iterables and not only ranges of integers, are there real-world use-cases where you need in range(len(a))?

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