new_contents: """
  An RNA string is a string formed from the alphabet containing 'A', 'C', 'G', and 'U'.
  
  Given a DNA string t corresponding to a coding strand, its transcribed RNA string u is formed by replacing
  all occurrences of 'T' in t with 'U' in u.
  
  Given: A DNA string t having length at most 1000 nt.
  
  Return: The transcribed RNA string of t.
  """
  
  if __name__ == '__main__':
  
      with open('data/rosalind_rna.txt', 'r') as f:
          sequence = f.read()
  
      print sequence.replace('T', 'U')
subject: Add solution to transcribing DNA into RNA