code: 
  
  
  def   SCREAMING_SNAKE_CASE__						(							snake_case_,	snake_case_,	snake_case_,	snake_case_,	snake_case_	)			->							None:
  
  				if target == 0:
  								answer.append(path.copy()	)
  				else:
  								for index in range(snake_case_,	len(snake_case_	)	):
  												if target >= candidates[index]:
  																path.append(candidates[index]	)
  																backtrack(snake_case_,	snake_case_,	snake_case_,	target - candidates[index],	snake_case_	)
  																path.pop(len(snake_case_	) - 1	)
  
  
  
  def   SCREAMING_SNAKE_CASE__						(							snake_case_,	snake_case_	)			->							list:
  				A__     :							List[Any]   				=[]  # type: list[int]
  				A__     :							List[str]   				=[]  # type: list[int]
  				backtrack(snake_case_,	snake_case_,	snake_case_,	snake_case_,	0	)
  				return answer
  
  
  
  def   SCREAMING_SNAKE_CASE__						(							)			->							None:
  				print(combination_sum([-8, 2.3, 0],	1	)	)
  
  
  if __name__ == "__main__":
  						import doctest
  
  						doctest.testmod()
  						main()
  
  
  
  
style_context: 
  
  
  def   SCREAMING_SNAKE_CASE__						(							snake_case_	)			->							int:
  				if number != int(snake_case_	):
  								raise ValueError('''factorial() only accepts integral values'''	)
  				if number < 0:
  								raise ValueError('''factorial() not defined for negative values'''	)
  				A__     :							Union[str, Any]   				=1
  				for i in range(1,	number + 1	):
  								value *= i
  				return value
  
  
  
  def   SCREAMING_SNAKE_CASE__						(							snake_case_	)			->							int:
  				if not isinstance(snake_case_,	snake_case_	):
  								raise ValueError('''factorial() only accepts integral values'''	)
  				if n < 0:
  								raise ValueError('''factorial() not defined for negative values'''	)
  				return 1 if n == 0 or n == 1 else n * factorial(n - 1	)
  
  
  if __name__ == "__main__":
  						import doctest
  
  						doctest.testmod()
  
  						__lowerCamelCase       :       Any				   =			int(input("Enter a positive integer: ").strip() or 0)
  						print(F"factorial{n} is {factorial(n)}")
  
  
  
  