






"""simple docstring"""



class        lowerCAmelCase__       :
   def __init__(						self	:     List[str]				,       snake_case__	:     Union[str, Any]				):


        '''simple docstring'''
        UpperCAmelCase__		:  str				=				data
        UpperCAmelCase__		:  Optional[Any]				=				None
        UpperCAmelCase__		:  Tuple				=				None




   def __str__(						self	:     Optional[int]				):


        '''simple docstring'''
        return f'{self.data}'




class        lowerCAmelCase__       :
   def __init__(						self	:     str				):


        '''simple docstring'''
        UpperCAmelCase__		:  List[str]				=				None
        UpperCAmelCase__		:  Tuple				=				None
   def __iter__(						self	:     Optional[Any]				):


        '''simple docstring'''
        UpperCAmelCase__		:  Union[str, Any]				=				self.head
        while node:
             yield node.data
             UpperCAmelCase__		:  Optional[Any]				=				node.next
   def __str__(						self	:     List[Any]				):


        '''simple docstring'''
        return "->".join([str(snake_case__				) for item in self]				)
   def __len__(						self	:     Union[str, Any]				):


        '''simple docstring'''
        return sum(1 for _ in self				)
   def 	__a				(						self	:     List[Any]				,       snake_case__	:     List[str]				):


        '''simple docstring'''
        self.insert_at_nth(0				,       snake_case__				)
   def 	__a				(						self	:     Dict				,       snake_case__	:     Dict				):


        '''simple docstring'''
        self.insert_at_nth(len(self				)				,       snake_case__				)
   def 	__a				(						self	:     Union[str, Any]				,       snake_case__	:     int				,       snake_case__	:     Optional[int]				):


        '''simple docstring'''
        UpperCAmelCase__		:  Any				=				len(self				)

        if not 0 <= index <= length:
             raise IndexError("list index out of range"				)
        UpperCAmelCase__		:  List[Any]				=				Node(snake_case__				)
        if self.head is None:
             UpperCAmelCase__		:  Union[str, Any]				=				new_node
        elif index == 0:
             UpperCAmelCase__		:  Optional[int]				=				new_node
             UpperCAmelCase__		:  int				=				self.head
             UpperCAmelCase__		:  Optional[int]				=				new_node
        elif index == length:
             UpperCAmelCase__		:  Optional[int]				=				new_node
             UpperCAmelCase__		:  str				=				self.tail
             UpperCAmelCase__		:  Any				=				new_node
        else:
             UpperCAmelCase__		:  Tuple				=				self.head
             for _ in range(0				,       snake_case__				):
                  UpperCAmelCase__		:  Optional[int]				=				temp.next
             UpperCAmelCase__		:  List[Any]				=				new_node
             UpperCAmelCase__		:  List[str]				=				temp.previous
             UpperCAmelCase__		:  Union[str, Any]				=				temp
             UpperCAmelCase__		:  List[Any]				=				new_node
   def 	__a				(						self	:     str				):


        '''simple docstring'''
        return self.delete_at_nth(0				)
   def 	__a				(						self	:     Any				):


        '''simple docstring'''
        return self.delete_at_nth(len(self				) - 1				)
   def 	__a				(						self	:     Optional[Any]				,       snake_case__	:     int				):


        '''simple docstring'''
        UpperCAmelCase__		:  str				=				len(self				)

        if not 0 <= index <= length - 1:
             raise IndexError("list index out of range"				)
        UpperCAmelCase__		:  Optional[int]				=				self.head  # default first node
        if length == 1:
             UpperCAmelCase__		:  str				=				None
        elif index == 0:
             UpperCAmelCase__		:  List[Any]				=				self.head.next
             UpperCAmelCase__		:  str				=				None
        elif index == length - 1:
             UpperCAmelCase__		:  Dict				=				self.tail
             UpperCAmelCase__		:  Any				=				self.tail.previous
             UpperCAmelCase__		:  Union[str, Any]				=				None
        else:
             UpperCAmelCase__		:  Tuple				=				self.head
             for _ in range(0				,       snake_case__				):
                  UpperCAmelCase__		:  str				=				temp.next
             UpperCAmelCase__		:  int				=				temp
             UpperCAmelCase__		:  List[Any]				=				temp.previous
             UpperCAmelCase__		:  int				=				temp.next
        return delete_node.data
   def 	__a				(						self	:     int				,       snake_case__	:     List[Any]				):


        '''simple docstring'''
        UpperCAmelCase__		:  List[Any]				=				self.head

        while current.data != data:  # Find the position to delete
             if current.next:
                  UpperCAmelCase__		:  Tuple				=				current.next
             else:  # We have reached the end an no value matches
                  raise ValueError("No data matching given value"				)

        if current == self.head:
             self.delete_head()

        elif current == self.tail:
             self.delete_tail()

        else:  # Before: 1 <--> 2(current) <--> 3
             UpperCAmelCase__		:  Optional[int]				=				current.next  # 1 --> 3
             UpperCAmelCase__		:  List[Any]				=				current.previous  # 1 <--> 3
        return data




   def 	__a				(						self	:     Optional[Any]				):


        '''simple docstring'''
        return len(self				) == 0




def      SCREAMING_SNAKE_CASE__    (   )->						None:






     '''simple docstring'''



     UpperCAmelCase__		:  Optional[int]				=				DoublyLinkedList()
     assert linked_list.is_empty() is True
     assert str(snake_case							) == ""

     try:
          linked_list.delete_head()
          raise AssertionError  # This should not happen.
     except IndexError:
          assert True  # This should happen.

     try:
          linked_list.delete_tail()
          raise AssertionError  # This should not happen.
     except IndexError:
          assert True  # This should happen.

     for i in range(10							):
          assert len(snake_case							) == i
          linked_list.insert_at_nth(snake_case       , i + 1							)
     assert str(snake_case							) == "->".join(str(snake_case							) for i in range(1       , 11							)							)

     linked_list.insert_at_head(0							)
     linked_list.insert_at_tail(11							)
     assert str(snake_case							) == "->".join(str(snake_case							) for i in range(0       , 12							)							)

     assert linked_list.delete_head() == 0
     assert linked_list.delete_at_nth(9							) == 10
     assert linked_list.delete_tail() == 11
     assert len(snake_case							) == 9
     assert str(snake_case							) == "->".join(str(snake_case							) for i in range(1       , 10							)							)


if __name__ == "__main__":
 from doctest import testmod

 testmod()










"""simple docstring"""



from transformers import PretrainedConfig




class        lowerCAmelCase__       (  __magic_name__					):
   SCREAMING_SNAKE_CASE_					      ='''custom'''
   def __init__(						self	:     Any				,       snake_case__	:     Any=1				,       **snake_case__	:     Optional[Any]				):


        '''simple docstring'''
        UpperCAmelCase__		:  List[str]				=				attribute
        super().__init__(**snake_case__				)




class        lowerCAmelCase__       (  __magic_name__					):
   SCREAMING_SNAKE_CASE_					      ='''custom'''
   def __init__(						self	:     List[str]				,       snake_case__	:     Tuple=1				,       **snake_case__	:     str				):


        '''simple docstring'''
        UpperCAmelCase__		:  List[str]				=				attribute


