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Classdata has various types so objects can havediferent types

collections o objects with identical

characteristics are collectively known as aclass

A class is just a user-dened data type.

An instance is just an object that belongs to aclass.

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Defning ClassesPython class is created by a class denition

Synta!

class name[ "expr[ #expr]$% ]! builtin datatype

suite 

&ote! The convention is to use initial capitalletters for the names of classes.

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's it si(ilar to structure)Classes -si(ilar to records o Pascal and

structs o C

*!

Class oo! a# b# c + ,# ene/# "0#1% data type that

can handleinteger# string

and list

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'nstantiating classesClasses "like unctions% are callable

' call the( they return an instance

A class is instantiated by calling the class

object!i + oo"%

print i.a# i.b# i.c

i+'nstance othe class oo

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*a(ple

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Attributes

an attribute is a way to get ro( one object toanother

objectna(e.attributena(e

objectna(e.attributena(e +another object

&ow point

toanotherobjectusingdot".%

Creatinganother

attributes byassign(ent

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Class attributes

class attribute - dened in the class# eithertetually in a class denition or later byassign(ent to an attribute reerence o theclass andstored in the class2s na(e space

*!

Class oo!

oo.a+0 Class attribute  oo.b+0

a 3 b+Classattribute

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Continue4

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'nstance attributeinstance attribute - dened in the instance# by

assign(ent# and is stored in the instance2sna(e space.

*!class oo!

  a + 0

i + oo"%

i.a => 0a+instanceattribute

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'nstance attributes

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5ening (ethods or aclass

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Constructor (ethod 6he 0st step ater the class is invoked is

instantiation process.

 77init77"class constructor% called duringinstantiating process and denes the object

i.e.# setting initial

values to theclass

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 77init77 (ethod

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*a(ple

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*rror

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Creating subclass-'nheritancePowerul aspects o 88P-ability to take an

already dened class and etend it withoutafecting the code

9e can etend :subclasses"'nheritance%

;ave a

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*a(ple

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ConclusionPython is ully object-oriented

9e can dene our own classes

 inherit ro( our own or built-in classes instantiate the classes we2ve dened

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