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- [Instructor] In this video,
I'd like to take a look

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at the String Types Format Method.

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Now, the F-strings or format
strings that we've been using

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throughout these videos so far,

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were added to the Python language back

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in Python version 3.6.

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As you can see here,

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I'm currently using Python version 3.7.3.

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And we do use the F-strings
throughout our videos and books.

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However, you will likely
encounter older Python code

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that uses the format methods.

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So I did wanna make sure that
I present that to you as well.

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Now the way the format method works

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is you create a format string,

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and then you invoke the format method

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on that string passing as
arguments to the method,

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the values that should be inserted.

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So for example, let me go ahead

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and paste in a sample snippet.

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Here you can see we have a format string

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and in this format string
the specifiers says

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that we would like to format a value

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as a floating point
number with two digits.

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So the right of the decimal point,

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we're invoking on that format
string, the format method

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and the value that we'd like to format

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in this case is 17.489.

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So as you can see, we do indeed
get two digits to the right

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of the decimal point in
the resulting strength.

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Now, you may be wondering what
if there are multiple values

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to be inserted?

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Well, you can have multiple
curly braced placeholders

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in your format string, and you
can supply multiple arguments

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to the format method.

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So here is a simple snippet,
in which all we wanna do

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is to insert the values Amanda and Cyan

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into the two placeholders
in the format string,

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and they will be inserted in the order

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that they're specified by default.

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So as you can see, we
get Amanda and then Cyan.

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Now when you're dealing
with internationalization

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and localization, you might find it handy

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to reference arguments in the
format methods parentheses

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by their position numbers,

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and then use different format strings

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depending on the language
that you're working with.

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So here's an example, in which
we have three placeholders,

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two of which have the
same index number in them,

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and one of which does not.

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And as you can see, we
only have two arguments,

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but the argument at index zero,
the first argument to format

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will be placed twice
into this format string.

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And the argument in the second position,

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index number one will be placed
once into the format string.

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So as you can see, we
get Happy Happy Birthday

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as a result of that.

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You can also use keyword
arguments as well,

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which can make these format
strings more readable.

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So for example, here
we have a format string

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in which we've defined keywords first

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and last as the names
of those placeholders.

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And then in the argument list,

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we can say first equals Amanda

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and that value will be placed here.

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And then we can say last equals Gray

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and that value will be placed here.

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And perhaps more interesting is the fact

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that of course, you can change the order.

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So last and first, same
arguments first and last.

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But now they come out in reverse order

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because by the name it's
inserted into the correct

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placeholder in the format string.