


"""simple docstring"""





from __future__ import annotations

from typing import Any



class 		snake_case_:






     def __init__(						self	:       Optional[int]       ,					UpperCamelCase_	:       Any       ,					UpperCamelCase_	:       Any					):  # noqa: A002
           lowerCAmelCase       :						int							= item
           lowerCAmelCase       :						Optional[int]							= next



class 		snake_case_:






     def __init__(						self	:       int					):
           lowerCAmelCase       :						Node | None							= None
           lowerCAmelCase       :						str							= 0






     def   lowerCamelCase__  (						self	:       int       ,					UpperCamelCase_	:       Any					):
           lowerCAmelCase       :						Optional[Any]							= Node(UpperCamelCase_       ,					self.head					)
           self.size += 1






     def   lowerCamelCase__  (						self	:       Any					):
           # Switched 'self.is_empty()' to 'self.head is None'
           # because mypy was considering the possibility that 'self.head'
           # can be None in below else part and giving error
           if self.head is None:
                 return None
           else:
                 lowerCAmelCase       :						Union[str, Any]							= self.head.item
                 lowerCAmelCase       :						int							= self.head.next
                 self.size -= 1
                 return item






     def   lowerCamelCase__  (						self	:       Optional[Any]					):
           return self.head is None






     def __str__(						self	:       List[str]					):
           if self.is_empty():
                 return ""
           else:
                 lowerCAmelCase       :						str							= self.head
                 lowerCAmelCase       :						Optional[int]							= ''''''
                 lowerCAmelCase       :						list[str]							= []
                 while iterate:
                       item_list.append(str(iterate.item					)					)
                       lowerCAmelCase       :						str							= iterate.next

                 lowerCAmelCase       :						Tuple							= ''' --> '''.join(UpperCamelCase_					)

                 return item_str






     def __len__(						self	:       Any					):
           return self.size






"""simple docstring"""





def   _snake_case    (    _snake_case					:      int      ):
      if not isinstance(_snake_case			, _snake_case      ):
            lowerCAmelCase       :						int							= f'''Input value of [number={number}] must be an integer'''
            raise TypeError(_snake_case      )
      if number < 0 or number % 2 == 1:
            return False
      lowerCAmelCase       :						int							= int(number**0.5      )
      return number == number_sqrt * (number_sqrt + 1)


if __name__ == "__main__":
 import doctest

 doctest.testmod()


