diff --git a/maths/binary_exponentiation_2.py b/maths/binary_multiplication.py
similarity index 83%
rename from maths/binary_exponentiation_2.py
rename to maths/binary_multiplication.py
index af8f776dd266..e1ef9c16f62d 100644
--- a/maths/binary_exponentiation_2.py
+++ b/maths/binary_multiplication.py
@@ -12,6 +12,15 @@
 
 
 def b_expo(a: int, b: int) -> int:
+    """
+    Find Binary Multiplication
+
+    >>> b_expo(2,3)
+    6
+
+    >>> b_expo(-2,3)
+    -6
+    """
     res = 0
     while b > 0:
         if b & 1:
@@ -24,6 +33,16 @@ def b_expo(a: int, b: int) -> int:
 
 
 def b_expo_mod(a: int, b: int, c: int) -> int:
+    """
+    Find Binary Exponiation Mode
+    Given method work like (a*b)%c
+
+
+    >>> b_expo_mod(2,3,4)
+    2
+    >>> b_expo_mod(2,3,3)
+    0
+    """
     res = 0
     while b > 0:
         if b & 1:
diff --git a/scripts/validate_filenames.py b/scripts/validate_filenames.py
index ed23f3907114..b52f4f52fc2d 100755
--- a/scripts/validate_filenames.py
+++ b/scripts/validate_filenames.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python3
+#!/usr/bin/env python
 import os
 
 try: