@property

@property implements full descriptor protocol (class that implements a dynamic protocol consisting of __set__, __get__, and __delete__) that shadows instance attributes of the same name when we try to access/set/delete instance attributes.

The signature of property constructor is property(fget=None, fset=None, fdel=None, doc=None). Few important things about instance attributes decorated by @property:

• If the attribute doesn’t have setter -> read-only attribute
• If the attribute doesn’t have deleter -> we can’t delete the attribute

class C:
   def __init__(self):
       self._x = 10

   @property
   def x(self):
       # called when we use obj.x
       return self._x

   @x.setter
   def x(self, v):
       # called when we use obj.x = v
       self._x = v

   @x.deleter
   def x(self, v):
       # called when we use obj.x = v
       self._x = v