Rohit Beriwal

Advanced Stuff about classes

Magic Methods

• These are in built methods in python and can be used for doing stuff on classes.
• These begin with “dunders” or “__”.

__init__ is called when objected is CREATED.
__repr__ is used for debugging/dev, by providing an unambiguous representation of the object.
__str__ is readable representation of the object, for display to the end user.

Property Decorator (getter method) & Setter Method & Deleter Method:

Lets us define a method, which can be accessed like an attribute. -> This can be useful in scenarios where class requires modification (some attribute must be updates, which is generally done through functions), but maintain the compatibility!.

NOTE: Setter and getter method SHOULD have SAME NAME.

This done using property decorator as:

class someclass():
  
  def __init__(self,var):
    self.var = var
    
  @property
  def var(self):
    # var has already been updates
    return self.var
    
  @var.setter
  def var(self, new_val):
    self.var = new_val
    
   @var.deleter
   def var(self):
      self.var = None

Deleter Method are called while deleting the class object, for eg:
```python someobj = someclass(somevar)

Below

del someobj ```