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All right.

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In this video I'm going to try and tricky.

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I want you to look at these expressions where I'm checking for equality right.

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I'm saying hey does true equal four one does empty string equal one due to race equal that are empty

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equal while each other now pause a video here and try to guess what the outcomes of this are going to

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be.

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Ready.

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By the way if you get one hundred percent on this wall.

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Good for you because if this was my first time learning python I wouldn't get this.

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Let's go home.

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Is that why you expected true evaluated so true because one evaluated to true an empty string.

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It goes to one evaluated to false that makes sense because they definitely don't equal each other right.

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An empty array doesn't equal to one and a 10 equals ten point zero and then both arrays that are empty

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equal to true.

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Now the reason I'm showing you here is that the double equals checks for equality or equality of value.

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That is if for example the first on true equals to one there's two different types one's an integer

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one's a boolean it will convert them into the same type.

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In this case this will be converted like this to a boolean value.

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And if you remember one is truth.

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So this will evaluate to True which is why we get true.

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What about the other one well on empty string is false see so it evaluates to false and false doesn't

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equal true.

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Right.

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Because we're checking for equality here.

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So one of these gets converted to the other's type.

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What about an empty array.

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Again an empty array is actually false see so that's not going to equal one a ten equals to a float

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of ten point 0.

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That gets converted to an integer or float.

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And they're going to equal each other and that's an expected behavior and then an empty array well equals

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an empty array.

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If I add in this array one two three one two three and I click Run I get an invalid syntax because I

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have this year let's run that again I get true that makes sense.

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Let's change this to one and see what happens if I click Run.

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All right still false Now this does get a little tricky right.

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Mm hmm.

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Should this have evaluated too.

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True but now we get false so this doesn't get converted in time vs. what we had here.

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Now don't get confused by this because this would be bad code if you're checking something like this.

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Well obviously you should be checking two types two of the same types together.

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Ideally when you use comparison operators or logical operators like this you're comparing two types

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and you're not letting Python do this type conversion and hopefully Python figures it out for us.

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But I hope the W quality makes sense because there's another check that we can do which is is and is

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well as a keyword in Python.

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What happens if we change all these equal signs to is do you think there will be a difference.

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Let's have a look.

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If I click Run I get false for everything.

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So what's the difference here.

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Equals checks for the equality in value such as one two three.

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Well that's has the same value as one two three in a list is actually checks if the location and memory

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where this value is stored is the same.

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Let's go through that.

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So true is that one note true is not one true is while only true.

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Right.

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That will be true.

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What about string one is that one.

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No.

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I mean for one to be a shrink that needs to be one.

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Right.

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Because the one string isn't only in one place in memory it's literally the exact same thing.

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What about this list.

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As a matter of fact lists two is array empty array.

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Is that or is this list a list.

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Well if we run this I still get false

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and this is a little tricky and also advanced every time I create a list it's added in memory somewhere.

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So this is in a location in memory but whenever I create a new list it's created in another location.

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So these are two completely different lists that live in different locations in memory.

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So it's going to check hey is this in the same memory space same bookshelf as that one.

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No that's not it.

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But why does this work for things like numbers and strings.

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And that's because underneath the hood these are types that are very simple that are in memory but in

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one location versus something like a list even though this might be the same list with the same items

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because this is a data structure every time we create it it's created in a new location so that even

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if we have a variable a that contains this list and by the way this will be the same for all our data

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structures like dictionaries sets topples.

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If I do B equals this and I check a is that B No they're created in a different memory space.

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So this where a points is in a different place than where B points.

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But if I do a equals to b I get true because this double equality checks only the values.

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Now this is a bit of a hard topic so you might have to watch this video a couple of times you might

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have to practice this a few times yourself but just keep in mind the difference between IS and double

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equals E is tends to be a little stricter.

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You're checking for the exact thing that you're looking for versus equality which checks the value.

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All right.

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That was a doozy.

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Clancy in the next video by.