


from __future__ import annotations

from typing import Any




class  A_ :







 """simple docstring"""





 def __init__(      self       :			str							,     _a       :			Any							,     _a       :			Any					)     ->      Optional[int]:  # noqa: A002
      UpperCAmelCase    :					List[Any]			=      item
      UpperCAmelCase    :					List[str]			=      next




class  A_ :







 """simple docstring"""





 def __init__(      self       :			List[str]					)     ->      Union[str, Any]:
      UpperCAmelCase    :					Dict			=      None
      UpperCAmelCase    :					str			=      0
 def 	_UpperCamelCase     (      self       :			str							,     _a       :			Any					)     ->      List[str]:
      UpperCAmelCase    :					Tuple			=      Node(_lowercase							,     self.head					)
      self.size += 1
 def 	_UpperCamelCase     (      self       :			List[str]					)     ->      Union[str, Any]:






      if self.head is None:
           return None
      else:
           UpperCAmelCase    :					Optional[Any]			=      self.head.item
           UpperCAmelCase    :					List[Any]			=      self.head.next
           self.size -= 1
           return item
 def 	_UpperCamelCase     (      self       :			List[Any]					)     ->      Any:
      return self.head is None
 def __str__(      self       :			Any					)     ->      Optional[int]:






      if self.is_empty():
           return ""
      else:
           UpperCAmelCase    :					Any			=      self.head
           UpperCAmelCase    :					Tuple			=      ""
           UpperCAmelCase    :					List[Any]			=      []
           while iterate:
                item_list.append(str(iterate.item					)					)
                UpperCAmelCase    :					int			=      iterate.next

           UpperCAmelCase    :					Any			=      " --> ".join(_lowercase					)

           return item_str

 def __len__(      self       :			Union[str, Any]					)     ->      Any:
      return self.size




from __future__ import annotations



def       __SCREAMING_SNAKE_CASE    (   __UpperCamelCase       :			str      )				->   bool:







  """simple docstring"""





  SCREAMING_SNAKE_CASE__     				= 42
  SCREAMING_SNAKE_CASE__     				= list(__UpperCamelCase      )
  SCREAMING_SNAKE_CASE__				,	SCREAMING_SNAKE_CASE__     				= _vector[:-1], int(_vector[-1]      )
  SCREAMING_SNAKE_CASE__     				= [int(__UpperCamelCase      ) for digit in __vector]

  vector.reverse()
  for i, digit in enumerate(__UpperCamelCase      ):
    if i & 1 == 0:
      SCREAMING_SNAKE_CASE__     				= digit * 2
      if doubled > 9:
        doubled -= 9
      check_digit += doubled
    else:
      check_digit += digit

  return check_digit % 10 == 0


if __name__ == "__main__":
   import doctest

   doctest.testmod()
   assert is_luhn('''79927398713''')
   assert not is_luhn('''79927398714''')
