_urllib_response_moved_attributes is a list with 4 elements: result of the function MovedAttribute, called with 3 arguments:
_urllib_response_moved_attributes = [ MovedAttribute ( "addbase" , "urllib" , "urllib.response" ) , MovedAttribute ( "addclosehook" , "urllib" , "urllib.response" ) , MovedAttribute ( "addinfo" , "urllib" , "urllib.response" ) , MovedAttribute ( "addinfourl" , "urllib" , "urllib.response" ) , ]