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Friends here we are going to

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see the difference between 'try except finally'

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and 'try except else' block. See already

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we know simple 'try' and 'except'; and 'try except Exception as e:',

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and also by adding known exceptions, right.

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See I mean, let me open my editor and I am going to save

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it as a simple script 'differences'.

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Yeah, I will take this one.

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Now see that. So already we know if I try to print something

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called variable 'a', right,

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Simply I am printing,

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"Exception occured".

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So guys, I am trying to print variable value 'a' but if that

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is not defined definitely you'll get an exception.

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That's why I'm handling in this way, instead of getting an

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error. It's correct.

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But the thing is what type of exception you are getting.

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So for that what you can do, you can add 'Exception as e' statement,

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and then you can print that error as well.

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Yes, I'm getting that. But if name is not defined, you know

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that what is the exception your Python is going to raise, that

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is 'NameError'.

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That's why I can handle known errors in this way

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also. Before your 'except Exception as e' block

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you can write in this way. Likewise any, right, any exception

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you can handle if you know the exceptions.

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"Variable is not defined". Now, which block is going to execute?

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[no audio]

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Right. This block is going to execute. Suppose if 'a' is defined

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then there is no exception,

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right? If 'a' is defined, no exception. Simply you are printing

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'a' variable value.

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It may be any value, right?

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That's fine.

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But if 'a' is not defined then only your Python is going to

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raise an exception, and if that exception is there here, then

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it will match and it will execute that 'except' block.

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That's fine.

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Likewise you can handle any number of exceptions if you know,

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and we know we have 'finally' as well.

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What is the usage of 'finally'?

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"This will execute

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always".

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Let me run it.

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See as of now 'a' is 10 and you're trying to print 'a' variable

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value, so there is no exception.

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So your 'try' block is success. If 'try' block is success, you're

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not getting an exception. That's fine.

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But if 'finally' is there, whether you are going to execute your

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'try' block successfully or not, or whether you are going to

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raise any exception or not,

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'finally' will always execute.

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So whatever the code is there in 'finally' that will always

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execute. That's fine.

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Now, what I am doing is, let me comment this.

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[no audio]

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Now I am going to write 'else' block.

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So I am writing simply 'print(

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"This will execute

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if there is no, if there is no exceptions

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in try block". That's it.

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Simple. 'finally' is always executing,

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but whereas if you add 'else' block after all your exceptions

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in your 'try' block what will happen means,

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if there is no exception, if everything goes good with your

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'try' block then only 'else' will also execute. See as of now,

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everything is good.

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I mean 'try' block is good, right. There is no chance to

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get any exception because 'a' is there and you're trying

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to print 'a' variable value.

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Now this will execute if there is no exception

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in your 'try' block.

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Now, what I am doing is, I am deleting 'a' variable value.

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Now, you are going to get an exception "a is not defined", that

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is 'NameError', "Variable is not defined".

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So if you get any exception in your 'try' block, then your

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'else' won't execute. Now see the result.

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You're not getting this message, 'else' block message.

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So simply if this is success,

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right, then only 'else' will execute. If 'try' will give

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you any, suppose if any exception occurred in 'try' then 'else'

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won't execute.

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Right. Fine.

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So, you know the difference 'else' and then 'finally'. And guys,

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you can also include after 'else', 'finally' also. That means

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actually 'try', 'except', any number of 'exception' blocks, then 'else'

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and 'finally' is the complete syntax if you want. So 'finally'

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and 'else' are optional. These two are optional, if you want

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you can include it.

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Right. Now see I'm running.

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What will happen?

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[no audio]

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'print(a)'. Some exception occurred, that is 'NameError'.

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So that's why "Variable is not defined", you are printing. So

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if exception occurred then anyway 'else' won't execute.

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So 'else' message you are not getting, but 'finally' you are getting

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because 'finally' will always will execute that.

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Now I am defining 'a' variable value. Now

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I'm running. See the result.

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So there is no exception in your 'try' block,

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that's why it is successful. Your 'try' is success. If 'try' is success

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'else' will execute.

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Yes, you are getting. Anyway, 'finally',

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'finally' will always execute.

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That's what it is doing.

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So this is the complete syntax for your 'try, except, and else,

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finally' block, right?

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So guys for time being try to remember the syntax if you

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write in this way what will happen. At what time, at what

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block is going to execute, right.

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So once we start with real-time scenarios there I will try

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to use this effectively, up to that I can't use it. For time being

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try to remember these syntaxes.

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Okay. Okay guys,

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Thank you for watching this video.

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[no audio]