code: def nextProperty(self, propuri):
          
          if propuri == self.properties[-1].uri:
              return self.properties[0]
          flag = False
          for x in self.properties:
              if flag == True:
                  return x
              if x.uri == propuri:
                  flag = True
          return None
docs: Returns the next property in the list of properties. If it's the last one, returns the first one.