code: def find(self, query, threshold=None):
          
          results = self.search(query, threshold)
          if results:
              return results[0][0]
          else:
              return None
docs: Simply return the best match to the query, None on no match.
  
          >>> from ngram import NGram
          >>> n = NGram(["Spam","Eggs","Ham"], key=lambda x:x.lower(), N=1)
          >>> n.find('Hom')
          'Ham'
          >>> n.find("Spom")
          'Spam'
          >>> n.find("Spom", 0.8)