



def 						SCREAMING_SNAKE_CASE__ (   lowercase					)  ->       bool:
   if not all(x.isalpha() for x in string					):
      raise ValueError("""String must only contain alphabetic characters."""					)

   snake_case				:    Optional[int]           =	sorted(string.lower()					)
   return len(__lowerCamelCase					) == len(set(__lowerCamelCase					)					)


if __name__ == "__main__":
       lowerCamelCase	:	int				=   input('Enter a string ').strip()

       lowerCamelCase	:	int				=   is_isogram(input_str)
       print(f"""{input_str} is {"an" if isogram else "not an"} isogram.""")











from math import pow




def 						SCREAMING_SNAKE_CASE__ (   lowercase						,lowercase						,lowercase						,lowercase						,lowercase						,)  ->       tuple[int, int]:
   if current_sum == needed_sum:
      # If the sum of the powers is equal to needed_sum, then we have a solution.
      solutions_count += 1
      return current_sum, solutions_count

   snake_case				:    Union[str, Any]           =	int(pow(lowercase						,lowercase					)					)
   if current_sum + i_to_n <= needed_sum:
      # If the sum of the powers is less than needed_sum, then continue adding powers.
      current_sum += i_to_n
      snake_case     , snake_case				:    List[Any]           =	backtrack(
          lowercase						,lowercase						,current_number + 1						,lowercase						,lowercase					)
      current_sum -= i_to_n
   if i_to_n < needed_sum:
      # If the power of i is less than needed_sum, then try with the next power.
      snake_case     , snake_case				:    str           =	backtrack(
          lowercase						,lowercase						,current_number + 1						,lowercase						,lowercase					)
   return current_sum, solutions_count




def 						SCREAMING_SNAKE_CASE__ (   lowercase						,lowercase					)  ->       int:
   if not (1 <= needed_sum <= 1000 and 2 <= power <= 10):
      raise ValueError(
          """Invalid input\n"""
          """needed_sum must be between 1 and 1000, power between 2 and 10."""					)

   return backtrack(lowercase						,lowercase						,1						,0						,0					)[1]  # Return the solutions_count


if __name__ == "__main__":
       import doctest

       doctest.testmod()





