code: def addFeature(self, feature):
          '''Appends Feature'''
          
          if isinstance(feature, Feature):
              self.features.append(feature)
          else:
              raise TypeError(
                  'feature Type should be Feature, not %s' % type(feature)f addFeature(self, feature):
          '''Appends Feature'''
          
          if isinstance(feature, Feature):
              self.features.append(feature)
          else:
              raise TypeError(
                  'feature Type should be Feature, not %s' % type(feature))
docs: Appends Feature