__builtin__ module in Python -

If I have a module test and I have to list all those functions, then I Do this:

  Import Test DIR (Test)   
 Unless I import the module, I do not use the functions defined in them I will. / P> 
 But all the functions in the  __Biltin___  module can be used without importing. But without the  import __builtin __  I am not able to do a  dir (__ builtin __) . Does this mean that we use the work without importing the whole module?  
  __builtin__ import zip  to  
 Is this something like the above? But if I do  del zip , then I  
 
 error of name: name 'zip' is not defined   
 Can anyone please explain this behavior?  
 
 As explained, names in python are first solved by viewing in local area , Then in any enclosed area, then in module-level area and finally in the namespace of built-in So there are special cases inherent in the way they are  not  imported within the scope of their modules, but if no name is found anywhere, then Python should have it  __ underlying __  Will look in  
 Note that you can access the content of this radius without importing it. To do this, a portable way  
  import system print (DIR (sys.modules ["__ builtin__"]))   
 in CPython, also  
  print (dir (__ buildins__))   
 but it is considered an implementation description and for other Python implementations or future versions May not be available.