code: def ucount(sitecol):
      
  
      ## a list for only catgs
      catg = [i for i in sitecol if i in "CATG"]
  
      ## find sites that are ambigs
      where = [sitecol[sitecol == i] for i in "RSKYWM"]
  
      ## for each occurrence of RSKWYM add ambig resolution to catg
      for ambig in where:
          for _ in range(ambig.size):
              catg += list(AMBIGS[ambig[0]])
  
      ## if invariant return " "
      if len(set(catg)) < 2:
          return " "
      else:
          ## get second most common site
          second = Counter(catg).most_common()[1][1]
          if second > 1:
              return "*"
          else:
              return "-"
docs: Used to count the number of unique bases in a site for snpstring.
      returns as a spstring with * and -