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meet python

Work with your list data

You often need to iterate over your list and perform some action on each item
as you go along. Of course, it is always possible to do something like this,
Define a list and populate its
which works but does not scale:
items with the names of two
movies.
fav_movies = ["The Holy Grail", "The Life of Brian"]

print(fav_movies[0]) This is the list-processing
Display the value of print(fav_movies[1]) code.
each individual list item
on the screen.

This code works as expected, making the data from the list appear on screen.
However, if the code is later amended to add another favorite movie to the list,
the list-processing code stops working as expected, because the list-processing code
does not mention the third item.

Big deal: all you need to do is add another print() statement, right?
Yes, adding one extra print() statement works for one extra movie, but
what if you need to add another hundred favorite movies? The scale of the
problem defeats you, because adding all those extra print() statements
becomes such a chore that you would rather find an excuse not to have to do.

It’s time to iterate

Processing every list item is such a common requirement that Python makes it
especially convenient, with the built-in for loop. Consider this code, which is
a rewrite of the previous code to use a for loop:
Define a list and populate it
just as you did before.
Use “for” to iterate
over the list, displaying
the value of each fav_movies = ["The Holy Grail", "The Life of Brian"]
individual item on
screen as you go. for each_flick in fav_movies: This is the list-processing

print(each_flick) code, using a for loop.

Using a for loop scales and works with any size list.

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