code: def unify_string_literals(js_string):
      
      n = 0
      res = ''
      limit = len(js_string)
      while n < limit:
          char = js_string[n]
          if char == '\\':
              new, n = do_escape(js_string, n)
              res += new
          else:
              res += char
              n += 1
      return res
docs: this function parses the string just like javascript
         for example literal '\d' in JavaScript would be interpreted
         as 'd' - backslash would be ignored and in Pyhon this
         would be interpreted as '\\d' This function fixes this problem.