diff --git a/user_data/strategies/util.py b/user_data/strategies/util.py
index 87ba469df..b7451ec83 100644
--- a/user_data/strategies/util.py
+++ b/user_data/strategies/util.py
@@ -9,4 +9,4 @@ def launcher(mode, coin, brain):
 
 def back_tester(date_time, coin, brain):
     date_time = date_time.replace(" ", "#") 	
-    subprocess.call("python3 " + EXECUTION_PATH + "back_tester.py " + date_time + " " + coin + " " + brain + "0.45 3", shell=True)
+    subprocess.call("python3 " +EXECUTION_PATH+ "back_tester.py " + date_time + " " + coin + " " + brain + "0.45 3", shell=True)