diff --git a/data_structures/arrays/equilibrium_index_in_array.py b/data_structures/arrays/equilibrium_index_in_array.py
index 8802db620..0717a45d9 100644
--- a/data_structures/arrays/equilibrium_index_in_array.py
+++ b/data_structures/arrays/equilibrium_index_in_array.py
@@ -3,7 +3,7 @@ Find the Equilibrium Index of an Array.
 Reference: https://www.geeksforgeeks.org/equilibrium-index-of-an-array/
 
 Python doctest can be run with the following command:
-python -m doctest -v equilibrium_index.py
+python -m doctest -v equilibrium_index_in_array.py
 
 Given a sequence arr[] of size n, this function returns
 an equilibrium index (if any) or -1 if no equilibrium index exists.