python - Classes, Hidden Attributes and Inheritance -

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I'm fairly new to OOP and Python. Many things that I know are taught themselves, so I would be grateful if you could just give me the link to read because I do not have the exact terminology, which I should seek to clarify my doubts.

This is my code yet: 

  square point (object): x = 2 y = 3 def __init __ (self, x, y): self.x_a = X self.y_b = Y class rectpoint (point): def __init __ (self, x, y): self X_1 = x self. Y_1 = y = self (x * x + y * y) ** 0.5 square circuit (point): pass a = point (3,4) b = circuit (3,4) c = racket point (3,4) print Ax # 2 Print Ai # 3 Print a.x_a # 3 Print a.y_b # 4 Print by Bx # 2 Print # 3 Print B.X_A # 3 Print B.I_B # 4 Print CX # 2 Print C # 3 Print C . X_1 # 3 Print CII # 4 print cdialist # 5.0 print cx_e # attribute er print ci_b # attribute error   
 attributes  self.x_a  and  self.y_b  Not available for Class  RectPoint  but  Circap  is available for?  
 Forward, why are  self.x  and  self.y  available for two sections  RectPoint < 
 < / Div>       
 "post-text" itemproc = "text"> 
 your  rectpoint __ init __  method  mask  to the  dot .__ init __  method. Because  dot .__ init __  has not been executed for the  RectPoint  examples,  self.x_a  and  self.y_b  attributes are never set. This is because Python first searches for the example, then the square, then the base class for the attributes. The methods are really special features, here. When creating an example of a class, then look at the  __ init __  method on the Python class, then on the base class.  
  Circuit  does not apply to themselves  __init __  hence  point .__ init __  is found and used , And  self.x_a  and  self.y_b   are  set.  
 You do specialty  class  attributes for  x  and  y ; The dragon finds these with the same search order; They are not set to the example, and eventually the  points  are found on the base class; Either because you have a subclass of  dot  example or  dot  and the base squares of that subclass were searched.  
 You  obviously  code overidade  __init __  method to  RectPoint .__ init___ :  < Pre>  class RectPoint (dot): def __init __ (self, x, y): super (rectpoint, self) .__ init __ (x, y) self. X_1 = x self. Y_1 = y self-dest = (x * x + y * y) ** 0.5   
 lets you enter the original  dot .__ init __  method here Call it first. This method then sets the  self.x_a  and  self.y_b  attributes, after which it will return and  the RectPoint .__ init __  method Features will set.  
 Includes everything in the description.

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