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Welcome to this tutorial on Python 2 Virgin versus Python 3.

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In all of the tutorials I'm going to demonstrate the examples on Python 3 but I would like to bring

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this topic up because there's a lot of confusion among beginners on which version to start off with

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and also hesitation in the Python community about switching to Python 3.

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The python to point all was gone was released in 2000 and the latest version there's two point seven

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which was released in 2010 and spurred the code Python team the python two point seven is slated to

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reach in the fly in the year 2020.

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That means there will be absolutely no more support from the code Python team even for security.

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Update coming to Python three point all this was released in 2008 and its latest version is three point

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six.

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Released in 2016 Python three point or is fundamentally different to previous Python releases because

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it is the first Python release that is not compatible with the old divisions programmers usually don't

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need to worry about minor updates.

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Say for example from Python two point six to two point seven as they usually only change the internal

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workings of Python.

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And this doesn't require programmers to change their syntax but the change between Python two point

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seven that does the final version of Python 2 and Python 3 on ore is much more significant because the

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code that worked in Python two point seven may need to be written in a different way to work in Python

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3 point 0.

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So if you're just picking up a language I recommend you to learn python 3 as its support will continue

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well into the future and is being used extensively and also it is not difficult to go back and learn

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the differences between the two languages.

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That is two point seven and three.

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If you need to use two point seven at some point in the future next.

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Python 3 has better unicode support in python 2 strings are stored as ASCII by default whereas in Python

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3 takes J strings are Unicode by default and Unicode is more versatile than ASCII.

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That's because unicode strings can store foreign language letters Roman letters and numerous symbols

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emojis etc. offering us more choices since so computers can understand only numbers the ASCII code is

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a numerical representation of a character such as E odd at and the table yard contains all 128 ASCII

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characters in decimal Octave.

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Hexadecimal plot meant coming to the unicode format Unicode is a versatile and robust character encoding

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that supports a word one like twenty eight thousand characters across contemporary and historic strips

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and symbols at.

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And if you want to store Strings as unicode in Python 2.

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In that case you can add a u just before the string.

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Here we see some of the symbols that are supported by unicode.

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We will now see how we can display the unicode characters in python 2 as well as Python 3 versions.

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So for that let's create a Jupiter notebook one in Python two equation.

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So I've created one notebook in python 2 version and and now one to create another book notebook in

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Python 3 version in Python 3 say for example I would like to display the copyright symbol and for that

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I will define a string is D 1 and assign the code for the symbol copyright and that symbol is zero Z

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or a nine.

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In order to encode this particular code for copy died in a format known as UTF 8 we need to append this

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code with the characters backslash.

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You will print this string losing the print function and execute so your code as you can see the display.

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The copyright symbol in Python 3.

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Now let's go to Python 2 and do the scene.

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So here is a python not to note book or let define a novice during your.

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And here is the code for the copyright symbol.

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It's 0 0 a 9.

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And as we have discussed before if you want to store Strings as unicode in python 2 We need to add you

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in front of the code.

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Also as we have discussed before not to encode this particular symbol in know the format UTF 8 we need

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to append the string the code with backslash you now we will print the string

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as to do so Python 3 uses Unicode by default which says programmers extra development time and we can

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easily type and display more characters directly in to our program.

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And if you would like the Python 3 code to be backwards compatible with Python 2 we can keep you before

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the string.

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There any python 3 non book.

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So in case you want to if you want the code in Python 3 to be backwards compatible with Python to weaken

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you keep the U before D string Python 2 has and Python 3 have different libraries since Python 3 is

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the future.

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Many of today's developers are creating libraries strictly for use with Python 3.

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Similarly many older libraries built for Python 2 are not forward compatible next.

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Python 3 has improved integer division in Python 2.

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If you write a number without the need digit after the decimal point it's it round your calculation

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down to the nearest whole number.

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Say for example we want to do wide the number 5 by 2 and then execute.

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As you can see here the question is do the result has been rounded to the nearest whole number.

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If you want the exact answer of 2.5 in that case you can drive floating point number.

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See for example flight point or divided by two and then execute.

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So here you have the expected result of 2.5 coming to Python 3.

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If you divide the same number 5 with two then execute we get the expected result of 2.5 without having

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to worry about adding those extra zeros next.

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By then 2 and Python 3 have different print statements and taxes.

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This is only a syntactical difference in Python 3 but it is a function say for example I print a statement

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the little one since print as a function in Python 3.

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I need to enclose this string in parenthesis and then execute in Python 2.

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Yet in the python tone more book.

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Print as a statement.

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So if I say and Hello What.

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This works perfectly fine without dependencies in Python 2.

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No coming back to it.

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Python 3 notebook so for example we give the print function without the parent this is let's see what

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happens.

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Code has been interrupted by the interpreter but the syntax Edward saying that the parent this is missing

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in the print function

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so we have discussed the differences between the two versions.

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Next we will discuss about the future module.

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Python 3.

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Introduce some Python two incompatible keywords and creatures that can be imported via the inbuilt future

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module in Python to say for example if we want the Python 3 versions integer division behavior in Python

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2.

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We can imported via the future module in order to import the division from the future module.

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This is how you do from underscored on the school future on this school on the school.

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Import division.

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So now if you tried to do the integer division in python 2 you'll get the expected result.

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And this is about the differences between the Python 2 and Python 3 versions.