Python Language Tutorial: Class Object Oriented Language - Part Seven

1. Firstly open python terminal and in Command Prompt of Windows and write code as below:
   
   class Student:
   
   o def __init__(self,name,age,grade):
   
   
   • self.name=name
   • self.age=age
   • self.grade = grade
     
     
     
     
   In above image __init__ is is default function of python.It also work as constructor of parameter in python. We can give many parameter to this function. Self parameter work as object to show all method and variable.
   
   
2. Now make Object of class and insert value of Student like below:
   
   Student1 = Student(“Neeraj”,12,”A”)
   
   
   
   Class Attributes:
   
   These Class attributes built-in attributes that can use for specific task.
   
   
   • __dict__: Dictionary containing the class's namespace.
   • __doc__: Class documentation string or none, if undefined.
   • __name__: Class name.
   • __module__: Module name in which the class is defined. This attribute is "__main__" in interactive mode.
   • __dict__: A possibly empty tuple containing the base classes, in the order of their occurrence in the base class list.
     
     
3. Now we example of all the above attributes.
   
   
   • print(Student.__doc__)
   • print(Student.__name__)
   • print(Student.__module__)
   • print(Student.__bases__)
   • print(Student.__dict__)
     
     
     
     
   These define the Class Concept according to their functionality.
   
   
4. Creation and Deletion of Object is easy in python as below code:
   
   
   • Student1 = Student("A",1,"A") // create student1 object
   • Student2 = Student("B",2,"B") // “”
   • del Student1 // delete the object student1
   • del Student2 //””
     
     
     
     
   Functions in Classes:
   
   class Student:
   
   
   • def __init__(self,name,age,grade):
     
     a. self.name=name
     b. self.age=age
     c. self.grade = grade
     
     
   • def displayStudent(self):
     
     a. return ("Student name is "+self.name+" and age is "+str(self.age))
     
     
   • student1=Student("BOB",21,"A")
     
   • student1.displayStudent()
     
     
   Output: 'Student name is BOB and age is 21'
   
   Class Method Built-In:
   
   
   • getattr(obj, name[, default]) : to access the attribute of object.
   • hasattr(obj,name) : to check if an attribute exists or not.
   • setattr(obj,name,value) : to set an attribute. If attribute does not exist, then it would be created.
   • delattr(obj, name) : to delete an attribute
   
   
5. Let's take an example of these Methods
   

   class Student:
   

   • def __init__(self,name,age
     
     
     • self.name=name
     • self.age=age
     • self.grade = grade
       
       
   • Student1 = Student("A",21,"A")
   • hasattr(Student1,"age")
   • hasattr(Student1,"marks")
   • setattr(Student1,"marks","75")
   • hasattr(Student1,"marks")
   • getattr(Student1,"grade")
   • getattr(Student1,"name")
   • delattr(Student1,"marks")
   • hasattr(Student1,"marks")
     
     
     

Sothis article has basic of class and mainly I define the Built-In features of Class in python. Remaining concept of OOPS work the same as another Programming language.