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Python Python Basics (Retired) Things That Count Things That Count

William Finch
William Finch
251 Points
Posted by William Finch
William Finch
251 Points

How would I create a new variable named "summary" that insert "days" into the string "I am {} days old!"?

How would I create the variable.

days_alive.py 
age = int(21)
days = int(age*52*7)

1 Answer

Cena Mayo
Cena Mayo
55,236 Points

Hi William,

You'd want to use string interpolation. That is, "evaluating a string literal containing one or more placeholders, yielding a result in which the placeholders are replaced with their corresponding values." (wikipedia)

In Python, it looks like this:

summary = "I am {} days old!".format(days)

So what's happening here is that Python knows that the '{}' in the summary variable is a placeholder. It fills that holder by calling the .format method with the days variable as an argument.

Hope that helps! Cena

William Finch
William Finch
251 Points
William Finch
William Finch
251 Points

Help out alot. Thank you!