How come a returned string can be interpreted as a function in python? -

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I learn the dragon by hard way and in the code snippet as I like below I've come. But I did not understand what is behind it, a function basically gives a string which is the function of the same name in the class. And it can call the function properly. 

  Exit import from the class game (object): def __init __ (auto, start): self. Start = RF game (self): next = self.start while correct: print "\ n --------" room = getattr (self, next) next = rooms () def a1 (self): print " You are redirecting to A2, you are redirecting to A2, "Return 'A2' Def A2 (Self): Print" You are in A2, Returns from Death Def Def Death (Self) '0) a_game = Game ('a1') a_game.play ()    
 
 
 What do you see  Getattr ()  is the result of builtin. Python is a high level language and what is more, an explanation Since all objects in the dragon are originally made in the form of hash-tables in memory, therefore Python has no large system.  
 This means that Python  runtime  and there is a way to do this  getattr ()  builtin receives  value  of the  getattr  builtin member in the first argument, which  Name  gets it as  string  The second argument is similar to  getattr (x, "y")  basically  xy  Is it Kin  getattr  also allows a safe approach where a default value can be given if a member is not actually present:  getattr (x, "y", "such a member No ") . If there is no member of  x  then  y  then  x.y  will be the cause of an  AttributeError . On the other hand,  gettattr (x, "y", "no such member is not there")  "no such member" will return the string and no exceptions will be raised.  
 In your case, the methods are placed in the  next  variable as strings and  getattr ()  builtin  rooms  Is kept in The  cell ()  is then applied and the names of the next methods are stored back and in the  next .  In  Loop until  Exit (0)  applies  game.death () . There is also a look at  
  setattr ()  and  hatter ()

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