US 8,691,490 B2  61  -continued  A repeating unit represented by the above-mentioned  gen- era! formula (7) is specifically the following.  H  H  H  H  (~o  (~o  ~OH  HO~OH  (++)  (µ)  if  ;==o  if  ’j=o  HO~OH  ~OH  (µ) (µ)  if  ’j=o  if  ’j=o  ~o  OH  ~o  OH  HO  HO  00  (~)  if  ’j=o  °>  b  (~)(~)  if  ’j=o  if  ’j=o  °>  °>  od  (~)(~)  if  ’j=o  if  ’j=o  °>  °>  d- ~  (~)(~)  if  ’j=o  if  ’j=o  °>  °>  ){)  ~ 