All language subtitles for 13. While Loop Example with User Input

So we had a script that checks if A is greater than 3 and prints out these operations.
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If that is true no let me go ahead and use a more real world example. Let's create a variable here called
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user name and give it a value of an empty string.
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And here lets check if username is different than the real user name which let's suppose it's py py.
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Now while that is true we want to ask the user
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to enter a username.
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So let's see what's going to happen.
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Enter user name.
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We got the prompts here by the input function py.
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Note we get enter user name again. Pyp maybe, no. Pypy.
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And so this time we don't get a prompt anymore.
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The execution of the program ends.
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So let me explain what's happened here.
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We declared the empty string to variable user name and then here we check if the value of the username
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variable is different than pypy.
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In this case it's different because this is an empty string and this is pypy.
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Therefore the first iteration will occur which is this one here.
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So in the first iteration we are asking the user to enter some inputs.
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This is what happens here in the first iteration.
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So enter user name was prompted and we entered pi.
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So pi now is the string that would the assigned to user name and the loop goes through the second iteration.
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So while the user name is different than pypy which is true in this case because user name for now
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it's py, the string py, so py is different than pypy, therefore go ahead and execute the body of the while
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loop again which is this one here.
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So ask one more time for the user name from the user.
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So user name the user enters pyp
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this time, the loop goes through the head through the beginning again and it checks if pyp is different
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than pypy, that's true, get the user name again.
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In this case we got pypy, so user name is pypy now.
The loop goes again while the user name is different
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than pypy.
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In this case that is not true because in this case the user name is equal to pypy, so pypy is different
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than pypy.
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No, that's false.
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So the third iteration this will be equal to false, and that is when the loop ends.
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So for loops end when their container is exhausted.
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And while loops ends when the condition is false.