diff --git a/prepare_cls.py b/prepare_cls.py
new file mode 100644
index 0000000..12b6905
--- /dev/null
+++ b/prepare_cls.py
@@ -0,0 +1,24 @@
+import fire
+import urllib.request
+from pathlib import Path
+
+lang_codes = ['fr', 'jp', 'en', 'de']
+
+def fetch_cls(url_prefix, cls_path="data/cls"):
+    """ Fetch CLS from server using basic auth
+        url_prefix should point to CLS stored as follow
+        "https://user:passwd@server/path/[en|fr|de|jp]/[dvd|music|books].[test|train|unlabeled].csv"
+    """
+    def fetch(url, CLS):
+        CLS.parent.mkdir(parents=True, exist_ok=True)
+        print("fetching", url, CLS)
+        urllib.request.urlretrieve(url, CLS)
+    for code in lang_codes:
+        for category in ['books', 'music', 'dvd']:
+            dir = Path(cls_path)/f'{code}-{category}'
+            fetch(f"{url_prefix}/{code}/{category}/train.csv", dir / f"{code}.train.csv")
+            fetch(f"{url_prefix}/{code}/{category}/test.csv", dir / f"{code}.test.csv")
+            fetch(f"{url_prefix}/{code}/{category}/unlabeled.csv", dir / f"{code}.unsup.csv")
+
+if __name__ == "__main__":
+    fire.Fire(fetch_cls)