'''simple docstring'''

import re
def       __UpperCamelCase	(       UpperCAmelCase					):

 if len(re.findall('''[ATCG]'''		,					UpperCAmelCase					)					) != len(UpperCAmelCase					):
  raise ValueError('''Invalid Strand'''					)

 return dna.translate(dna.maketrans('''ATCG'''		,					'''TAGC'''					)					)


if __name__ == "__main__":
  import doctest

  doctest.testmod()


'''simple docstring'''

def       __UpperCamelCase	(       UpperCAmelCase					):
 if not all(x.isalpha() for x in string					):
  raise ValueError('''String must only contain alphabetic characters.'''					)

 lowercase__    :   Tuple						= sorted(string.lower()					)
 return len(UpperCAmelCase					) == len(set(UpperCAmelCase					)					)


if __name__ == "__main__":
  __a:			Union[str, Any]	       =       input("""Enter a string """).strip()

  __a:			Tuple	       =       is_isogram(input_str)
  print(F'{input_str} is {"an" if isogram else "not an"} isogram.')

