code: 
  
  
  
  
  
  
  """simple docstring"""
  import math
  
  
  def        A	(							__snake_case:   int     )						->		bool:
  
         """simple docstring"""
  
  
  
  
  
         if 1 < number < 4:
                # 2 and 3 are primes
                return True
         elif number < 2 or number % 2 == 0 or number % 3 == 0:
                # Negatives, 0, 1, all even numbers, all multiples of 3 are not primes
                return False
  
         # All primes number are in format of 6k +/- 1
         for i in range(5   ,    int(math.sqrt(__snake_case     ) + 1     )   ,    6     ):
                if number % i == 0 or number % (i + 2) == 0:
                       return False
         return True
  
  
  def        A	(							__snake_case:   int = 2_0_0_0_0_0_0     )						->		int:
  
         """simple docstring"""
  
  
  
  
  
         return sum(num for num in range(3   ,    __snake_case   ,    2     ) if is_prime(__snake_case     )     ) + 2 if n > 2 else 0
  
  
  if __name__ == "__main__":
   print(f"""{solution() = }""")
style_context: 
  
  
  
  
  
  
  """simple docstring"""
  def        A	(							__snake_case:   Dict   ,    __snake_case:   Tuple     )						->		int:
  
         """simple docstring"""
  
  
  
  
  
         sequence.append(__snake_case     )
  
         __magic_name__										=						0
         while sequence[index] != target:
                index += 1
  
         sequence.pop()
  
         if index == len(__snake_case     ):
                return None
  
         return index
  
  
  if __name__ == "__main__":
   snake_case   :   Dict    		=		input("""Enter numbers separated by comma:\n""").strip()
   snake_case   :   List[str]    		=		[int(item) for item in user_input.split(""",""")]
  
   snake_case   :   Union[str, Any]    		=		input("""Enter a single number to be found in the list:\n""")
   snake_case   :   str    		=		int(target_input)
   snake_case   :   Any    		=		sentinel_linear_search(sequence, target)
   if result is not None:
    print(f"""{target} found at positions: {result}""")
   else:
    print("""Not found""")