diff --git a/mteb/tasks/pair_classification/multilingual/pub_chem_wiki_pair_classification.py b/mteb/tasks/pair_classification/multilingual/pub_chem_wiki_pair_classification.py
index f02cb4db76..23eec9e7d1 100644
--- a/mteb/tasks/pair_classification/multilingual/pub_chem_wiki_pair_classification.py
+++ b/mteb/tasks/pair_classification/multilingual/pub_chem_wiki_pair_classification.py
@@ -60,7 +60,7 @@ class PubChemWikiPairClassification(AbsTaskPairClassification):
 """,
     )
 
-    def dataset_transform(self) -> None:
+    def dataset_transform(self, num_proc: int = 1) -> None:
         _dataset = {}
         for lang in self.hf_subsets:
             _dataset[lang] = {}