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What does this do again {} ?

So i am learning python but i see craig use this alot of time " {} " and as far as i remember he called it a placeholder. But what does it do?

1 Answer

Cooper Runstein
Cooper Runstein
11,850 Points

Most likely you're seeing it used in situations like this:

string = "Hello {}".format("world")

The {} serves as a placeholder for the text that you insert with the format function. So right now, if you printed out the variable string, it would return "Hello world".

string2 = "Hello {}".format("frederik")

Here string2 becomes "Hello frederik"

Kailash Seshadri
Kailash Seshadri
3,087 Points

Unless you specify world, or frederick, as a variable e.g:

world = "Bob"
string = "Hello {}".format(world)

In this case, a print (string) will output Hello Bob

NB: Notice that in the .format brackets, the word world now doesn't have a "". This is so that the format does not treat the world as a string, and instead as a variable. So:

world = "Bob"
string = "Hello {}".format("world")

In this case, a print(string) will output Hello world, because the world is now treated as a string, not as a variable.