diff --git a/pairtools/lib/dedup.py b/pairtools/lib/dedup.py
index 92e99de..335270b 100644
--- a/pairtools/lib/dedup.py
+++ b/pairtools/lib/dedup.py
@@ -5,7 +5,7 @@
 from scipy.sparse import coo_matrix
 from scipy.sparse.csgraph import connected_components
 
-from . import dedup_cython, pairsam_format
+from . import pairsam_format
 from .stats import PairCounter
 
 from .._logging import get_logger
@@ -339,6 +339,8 @@ def streaming_dedup_cython(
     -------
 
     """
+    from . import dedup_cython
+    
     maxind = max(c1ind, c2ind, p1ind, p2ind, s1ind, s2ind)
     if bool(extra_cols1) and bool(extra_cols2):
         maxind = max(maxind, max(extra_cols1), max(extra_cols2))