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Inheritance is extremely important in C++ and Java primarily because of the use of runtime polymorphism in program design.However, due to the lack of polymorphism, inheritance in Python is not nearly as important as in those other two languages. Although it may have some other uses, inheritance in Python appearsmainly to be a convenient way to reduce the amount of typing required to write a program.

According to tutorialspoint--Python Objected Oriented , Python inheritance is

"The transfer of the characteristics of a class to other classes that are derived from it."

While that can sometimes be a useful capability, it is simply one of many useful capabilities that exist in Python

Multiple inheritance

C++ supports a concept know as multiple inheritance , which often results in significant programming errors for novice programmers. Multipleinheritance is so problematic that the designers of Java excluded it from the language and replaced it with a safer alternative known as the Java interface .

Python also supports multiple inheritance. Because of the general lack of safety nets in Python, in my opinion, multiple inheritance is more problematicfor novice programmers in Python than in C++. My advice -- don't use Python multiple inheritance for any serious programming effort until you become a verycapable Python programmer.

Very brief coverage

As a result of the issues mentioned above, this module will provide only a very brief treatment of inheritance in Python. If you need to learn more aboutinheritance, I will refer you to the following documents that are available on the web as of October 2014.

Discussion and sample code

I will present and explain a simple program to give you a taste of inheritance. A complete listing of the program is provided in Listing 6 . The output produced by running the program is shown in Figure 4 . As usual, I will break the program down and explain it in fragments.

Define the superclass

Listing 1 defines a class named Superclass that will be the superclass or the base class for another class named Subclass . In other words, the class named Subclass will inherit from the class named Superclass or will extend the class named Superclass , whichever jargon you prefer. (A visualization of the program uses the word extends to indicate inheritance.)

Depending on your preferred jargon, Superclass will be the base class or the superclass . Subclass will be the derived class or the subclass .

Listing 1 . Define the superclass.
#Define the superclass class Superclass(object):superclassVar = Truedef __init__(self,name): Superclass.superclassVar = nameself.friend = "Tom"

The code in Listing 1 creates a class variable named superclassVar and initializes its value to True .

The code in Listing 1 also defines an initializer or constructor method named __init__ . When this method is executed, it changes the value stored in superclassVar from True to the value of an incoming parameter named name .

The __init__ method also creates an instance variable named friend in the object referred to by self and initializes that variable to contain "Tom" .

Questions & Answers

general equation for photosynthesis
Ojasope Reply
6CO2 + 6H2O + solar energy= C6H1206+ 6O2
Anastasiya
meaning of amino Acids
AJAYI Reply
a diagram of an adult mosquito
mubarak Reply
what are white blood cells
Mlungisi Reply
white blood cell is part of the immune system. that help fight the infection.
MG
what about tissue celss
Mlungisi
Cells with a similar function, form a tissue. For example the nervous tissue is composed by cells:neurons and glia cells. Muscle tissue, is composed by different cells.
Anastasiya
I need further explanation coz celewi anything guys,,,
Calvin Reply
hey guys
Isala
on what?
Anastasiya
hie
Lish
is air homogenous or hetrogenous
damiane Reply
homogenous
Kevin
why saying homogenous?
Isala
explain if oxygen is necessary for photosynthesis
Allice Reply
explain if oxygen is necessary for photosynthesis
Allice Reply
Yes, the plant does need oxygen. The plant uses oxygen, water, light, and produced food. The plant use process called photosynthesis.
MG
By using the energy of sunlight, plants convert carbon dioxide and water into carbohydrates and oxygen by photosynthesis. This happens during the day and sunlight is needed.
NOBLE
no. it s a product of the process
Anastasiya
yet still is it needed?
NOBLE
no. The reaction is: 6CO2+6H20+ solar energy =C6H12O6(glucose)+602. The plant requires Carbon dioxyde, light, and water Only, and produces glucose and oxygen( which is a waste).
Anastasiya
what was the question
NOBLE Reply
joining
Godfrey
the specific one
NOBLE
the study of non and living organism is called.
Godfrey
Is call biology
Alohan
yeah
NOBLE
yes
Usher
what Is ecology
Musonda Reply
what is a cell
Emmanuel Reply
A cell is a basic structure and functional unit of life
Ndongya
what is biolgy
Hawwi Reply
is the study of living and non living organisms
Ahmed
may u draw the female organ
MARTIN Reply
i dont understand
Asal
:/
Asal
me too
DAVID
anabolism and catabolism
Sani Reply
Anabolism refers to the process in methabolism in which complex molecules are formed "built" and requires energy to happen. Catabolism is the opposite process: complex molecules are deconstructed releasing energy, such as during glicolysis.
Anastasiya
Explain briefly independent assortment gene .
Otu Reply
hi
Amargo
hi I'm Anatalia
Joy
what do you mean by pituitary gland
Digambar
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Source:  OpenStax, Itse 1359 introduction to scripting languages: python. OpenStax CNX. Jan 22, 2016 Download for free at https://legacy.cnx.org/content/col11713/1.32
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