code: def sim(self, src, tar):
          
          if src == tar:
              return 1.0
          if not src or not tar:
              return 0.0
          return (
              len(src) / len(tar) if len(src) < len(tar) else len(tar) / len(src)
          )
docs: Return the length similarity of two strings.
  
          Length similarity is the ratio of the length of the shorter string to
          the longer.
  
          Parameters
          ----------
          src : str
              Source string for comparison
          tar : str
              Target string for comparison
  
          Returns
          -------
          float
              Length similarity
  
          Examples
          --------
          >>> cmp = Length()
          >>> cmp.sim('cat', 'hat')
          1.0
          >>> cmp.sim('Niall', 'Neil')
          0.8
          >>> cmp.sim('aluminum', 'Catalan')
          0.875
          >>> cmp.sim('ATCG', 'TAGC')
          1.0