A for loop in Python doesn’t require an index ... It takes an iterable and upon each iteration generates a tuple of the index and the object at that index: x = [3,1,4,1,5,9] for index, n ...

If you’ve ever written any Python at all, the chances are you ... iterators can work on the principle of lazy evaluation: as you loop over an iterator, values are generated as required.

In general, for loops are used when you know exactly how many times you plan to run a loop; a while loop is used when the number of iterations is uncertain. Note: The if statement is like a single ...

Python is a general-purpose programming ... that can store the contents of each file on each iteration.>>>file_in = list() Use a "for" loop to cycle through each file name in the file name list.