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Python Introducing Lists Meet Lists Indexing

Idrees Richard
Idrees Richard
166 Points

Hi All,What is actually the purpose of the .format () command? I did some researching online and cant seem to understand

I'm not really sure why we actually need to use the .format(books[0])? rather than just printing out books[0]?

Thanks!

2 Answers

Alex Koumparos
seal-mask
.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,887 Points

Hi Anas,

There are two basic ways of combining some string literal (i.e., hard coded text) and some computed or stored value (e.g., something in a variable):

The first, format() is used for string interpolation. This allows us to inject some code into a string and have it evaluated at runtime. For example:

my_variable = "world"
print("hello, {}".format(my_variable))

In most cases it is functionally equivalent to the second, string concatenation, using the + operator:

my_variable = "world"
print("hello, " + my_variable)

and which one you'd use depends on personal preference or house style.

Later on, you'll learn some neat ways that you can use interpolation with tuples and dictionaries that you can't easily replicate with concatenation.

Hope that helps

Cheers

Alex

Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hey Alex, very nice answer!!! I see a typo in the first print statement :sunglasses: though :smile: