diff --git a/dataset.py b/dataset.py
index 732da4b..c4d3e62 100644
--- a/dataset.py
+++ b/dataset.py
@@ -71,9 +71,13 @@ def get_user_chunks(user_flow, window=10):
     #     domains.pop(-1)
     #     flows.pop(-1)
     # return domains, flows
+    result = []
     chunk_size = (len(user_flow) // window)
-    last_inrange = chunk_size * window
-    return np.split(user_flow.head(last_inrange), chunk_size) if chunk_size else []
+    for i in range(chunk_size):
+        result.append(user_flow.iloc[i * window:(i + 1) * window])
+    if result and len(result[-1]) != window:
+        result.pop()
+    return result
 
 
 def get_domain_features(domain, vocab: dict, max_length=40):
@@ -153,7 +157,9 @@ def create_dataset_from_lists(chunks, vocab, max_len):
     logger.info("  compute domain features")
     domain_features = []
     for ds in tqdm(map(lambda f: f.domain, chunks)):
-        assert min(np.atleast_3d(ds).shape) > 0, f"shape of 0 for {ds}"
+        # TODO: fix this correctly
+        # assert min(np.atleast_3d(ds).shape) > 0, f"shape of 0 for {ds}"
+        if not ds: continue
         domain_features.append(np.apply_along_axis(get_domain_features_reduced, 2, np.atleast_3d(ds)))
     domain_features = np.concatenate(domain_features, 0)
     logger.info("  compute flow features")
@@ -161,7 +167,7 @@ def create_dataset_from_lists(chunks, vocab, max_len):
     logger.info("  select hits")
     hits = np.max(np.stack(map(lambda f: f.virusTotalHits, chunks)), axis=1)
     logger.info("  select names")
-    names = np.unique(np.stack(map(lambda f: f.user_hash, chunks)), axis=1)
+    names = np.unique(np.stack(map(lambda f: f.user_hash, chunks)))
     logger.info("  select servers")
     servers = np.max(np.stack(map(lambda f: f.serverLabel, chunks)), axis=1)
     logger.info("  select trusted hits")
diff --git a/hyperband.py b/hyperband.py
index c9f30c2..d01ce11 100644
--- a/hyperband.py
+++ b/hyperband.py
@@ -68,7 +68,7 @@ class Hyperband:
             r = self.max_iter * self.eta ** (-s)
 
             # n random configurations
-            T = [self.get_params() for i in range(n)]
+            T = [self.get_params() for _ in range(n)]
 
             for i in range((s + 1) - int(skip_last)):  # changed from s + 1