code: def transform(self, transformer):
          
          self.transformers.append(transformer)
          from languageflow.transformer.tagged import TaggedTransformer
  
          if isinstance(transformer, TaggedTransformer):
              self.X, self.y = transformer.transform(self.sentences)
          if isinstance(transformer, TfidfVectorizer):
              self.X = transformer.fit_transform(self.X)
          if isinstance(transformer, CountVectorizer):
              self.X = transformer.fit_transform(self.X)
          if isinstance(transformer, NumberRemover):
              self.X = transformer.transform(self.X)
  
          if isinstance(transformer, MultiLabelBinarizer):
              self.y = transformer.fit_transform(self.y)
docs: Add transformer to flow and apply transformer to data in flow
  
          Parameters
          ----------
          transformer : Transformer
              a transformer to transform data