All language subtitles for 3. String Formatting with Multiple Variables

Previously I introduced you how to dynamically insert the value of a variable inside a string.
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So here we constructed "Hello" and whatever value the user entered in the input function.
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So this worked with Python 2 and 3.
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This works with Python 3.6 and later versions. Now what if you want to insert more than one value inside
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a string?
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How to do that?
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For example let's say the first input function will ask us for the name and the second will ask us for
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the surname, let's call this variable name.
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And this one surname. To use this version of string formatting with two variables you'd need to do this:
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Instead of just one variable,
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you need to use round brackets and then enter all the variables you want to insert in the string.
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Name and surname in this case.
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Now if you execute this you're going to get an error.
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So you need to do something more there.
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Let's say Ardit Sulce and you got a type error.
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Not all arguments converted during string formatting.
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Which means that the arguments are Name and Surname.
Not all of them were converted because only name
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was converted because you only had one place holder here.
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%s, you want to have two placeholders, one for surname too.
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If you execute that,
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well we get another error.
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But that's not related to this line here.
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This line is perfectly fine.
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It works.
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Why does it work?
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Well, because you can see that the error happened,
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so this is where the trace back starts.
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You see that of the error happens in file basics.py which is the file where we have the code in
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line 5 which means that above line 5
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everything is OK.
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So this line now has passed the error checking.
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It's free of errors. So this is the line that has the error,
and it's a name error, name user input is
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not defined.
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So this user inputs here has not been defined in our code.
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We don't have a variable with that name.
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We're just using it here but we didn't define it and here is a trick.
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If you don't want to execute that line, you can comment it out.
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,So by adding this symbol here, Python will ignore this line, it will treat it as a comment, not as code.
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So save the script, execute, enter your input as a user.
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And this is the output we get this time.
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So that was a good exercise on how to fix errors.
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Now back to our string formatting operations.
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Let's see how this now will work with two variables.
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So user inputs it's not a variable anymore.
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We want to use name.
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So f"Hello" , and then we want to have a space here.
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So this is a white space, so name whitespace , and it's as easy as that.
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Execute,
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and you get the output Hello
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Ardit Sulce.
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So that's the message variable, the string of the message variable.
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So in this way you can put as many variables as you like.
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For example: What's up .
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When could be a variable "today".
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The string "today" is part of the when variable.
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The when variable will be replaced in here by the value that it has.
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It currently has.
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Which is today.
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Execute that
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and that's how it works.
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And that's what you need to know about string formatting
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in Python.