diff --git a/labs06/task02.py b/labs06/task02.py
index 69ddaa6..16f0e26 100755
--- a/labs06/task02.py
+++ b/labs06/task02.py
@@ -13,7 +13,7 @@ def most_common_room_number(dane):
     return mode(dane.Rooms)
 
 def cheapest_flats(dane, n):
-    return dane.sort_values(by=["Expected"]).head(n)
+    return dane.sort_values(by="Expected").head(n)
 
 def find_borough(desc):
     dzielnice = ['Stare Miasto',
@@ -67,6 +67,6 @@ def main():
 
     print("Średnia cena mieszkania 3-pokojowego, to: {}"
           .format(mean_price(dane, 3)))
-    
+
 if __name__ == "__main__":
      main()