"""simple docstring"""





from __future__ import annotations

from typing import Generic, TypeVar

_UpperCamelCase       :						Dict     =   TypeVar("T")


class 					UpperCAmelCase_     (   Generic[T]):


      def __init__(       self		,      a							)	-> Dict:
             lowercase__      :		Tuple          =     data  # Assign data
             lowercase__      :		Node[T] | None          =     None  # Initialize next as null
             lowercase__      :		Node[T] | None          =     None  # Initialize prev as null





class 					UpperCAmelCase_     (   Generic[T]):


      def __init__(       self							)	-> None:
             lowercase__      :		Node[T] | None          =     None


      def 		_UpperCAmelCase	(       self		,      a							)	-> None:
             if self.head is None:
                    lowercase__      :		int          =     Node(a							)
             else:
                    lowercase__      :		str          =     Node(a							)
                    lowercase__      :		Tuple          =     new_node
                    lowercase__      :		Optional[Any]          =     self.head
                    lowercase__      :		Tuple          =     None
                    lowercase__      :		Union[str, Any]          =     new_node


      def 		_UpperCAmelCase	(       self							)	-> T | None:
             if self.head is None:
                    return None
             else:
                    assert self.head is not None
                    lowercase__      :		List[str]          =     self.head.data
                    lowercase__      :		List[Any]          =     self.head.next
                    if self.head is not None:
                           lowercase__      :		List[str]          =     None
                    return temp


      def 		_UpperCAmelCase	(       self							)	-> T | None:
             return self.head.data if self.head is not None else None


      def __len__(       self							)	-> int:
             lowercase__      :		Dict          =     self.head
             lowercase__      :		List[Any]          =     0
             while temp is not None:
                    count += 1
                    lowercase__      :		Dict          =     temp.next
             return count


      def 		_UpperCAmelCase	(       self							)	-> bool:
             return self.head is None


      def 		_UpperCAmelCase	(       self							)	-> None:
             print('stack elements are:'							)
             lowercase__      :		Any          =     self.head
             while temp is not None:
                    print(temp.data		,      end='->'							)
                    lowercase__      :		Tuple          =     temp.next


# Code execution starts here
if __name__ == "__main__":
       # Start with the empty stack
       _UpperCamelCase       :						Stack[int]     =   Stack()

       # Insert 4 at the beginning. So stack becomes 4->None
       print("Stack operations using Doubly LinkedList")
       stack.push(4)

       # Insert 5 at the beginning. So stack becomes 4->5->None
       stack.push(5)

       # Insert 6 at the beginning. So stack becomes 4->5->6->None
       stack.push(6)

       # Insert 7 at the beginning. So stack becomes 4->5->6->7->None
       stack.push(7)

       # Print the stack
       stack.print_stack()

       # Print the top element
       print("\nTop element is ", stack.top())

       # Print the stack size
       print("Size of the stack is ", len(stack))

       # pop the top element
       stack.pop()

       # pop the top element
       stack.pop()

       # two elements have now been popped off
       stack.print_stack()

       # Print True if the stack is empty else False
       print("\nstack is empty:", stack.is_empty())


"""simple docstring"""





from ..utils import DummyObject, requires_backends


class 					UpperCAmelCase_     (   metaclass=_a):
      lowerCamelCase__		:   List[str]			  =  ["torch", "transformers", "k_diffusion"]


      def __init__(       self		,      *a		,      **a							)	-> Dict:
             requires_backends(self		,      ['torch', 'transformers', 'k_diffusion']							)


      @classmethod
      def 		_UpperCAmelCase	(       cls		,      *a		,      **a							)	-> Tuple:
             requires_backends(cls		,      ['torch', 'transformers', 'k_diffusion']							)


      @classmethod
      def 		_UpperCAmelCase	(       cls		,      *a		,      **a							)	-> Any:
             requires_backends(cls		,      ['torch', 'transformers', 'k_diffusion']							)

