feat(dataloader): prints shape of data frame created

dataloader.py

@@ -255,6 +255,7 @@ class dataloader:
                 self.df = pd.merge(self.df, r_df, how="left")
             else:
                 self.df = r_df
+        print(f" data size is {self.df.shape}")
         # define ids
         self.ids = list(self.df.id.unique())
         if not use_tsv: