diff --git a/Trajectories/segments.py b/Trajectories/segments.py
index 87e084a37a1bc30d7badc4dc1e2af1acb33b2cf2..7bdbfccd4654c71dee0e10fa535b420727c70729 100755
--- a/Trajectories/segments.py
+++ b/Trajectories/segments.py
@@ -11,12 +11,13 @@ segment is in ascending order.
 
 """
 
-import graph_tool
 import time
 import sys
 import pathlib
 from os import path
 
+import graph_tool
+
 if len(sys.argv) != 3:
     sys.exit("Required arguments: input-edgelist-file output-graph-tool-file")