Fixed import error

turftopic/base.py

@@ -6,6 +6,7 @@
 from rich.table import Table
 from sentence_transformers import SentenceTransformer
 from sklearn.base import BaseEstimator, TransformerMixin
+from sklearn.exceptions import NotFittedError
 
 from turftopic.data import TopicData
 from turftopic.encoders import ExternalEncoder
@@ -291,17 +292,21 @@ def prepare_topic_data(
         if embeddings is None:
             embeddings = self.encode_documents(corpus)
         try:
-            document_topic_matrix = self.transform(corpus, embeddings=embeddings)
+            document_topic_matrix = self.transform(
+                corpus, embeddings=embeddings
+            )
         except (AttributeError, NotFittedError):
-            document_topic_matrix = self.fit_transform(corpus, embeddings=embeddings)
-        dtm = self.vectorizer.transform(corpus) # type: ignore
+            document_topic_matrix = self.fit_transform(
+                corpus, embeddings=embeddings
+            )
+        dtm = self.vectorizer.transform(corpus)  # type: ignore
         res: TopicData = {
             "corpus": corpus,
             "document_term_matrix": dtm,
             "vocab": self.get_vocab(),
             "document_topic_matrix": document_topic_matrix,
             "document_representation": embeddings,
-            "topic_term_matrix": self.components_, # type: ignore
+            "topic_term_matrix": self.components_,  # type: ignore
             "transform": getattr(self, "transform", None),
         }
         return res