tqdm now optional

wani.py

@@ -12,7 +12,11 @@ import concurrent.futures
 import tempfile
 
 from msd_translate import MSD_TRANSLATE
-from tqdm import tqdm
+
+try:
+    from tqdm import tqdm
+except ImportError:
+    tqdm = lambda x: x
 
 
 MAX_NUM_COMPONENTS = 5