diff --git a/batch_file_rename.py b/batch_file_rename.py
index bab145e909b..613637fa53e 100644
--- a/batch_file_rename.py
+++ b/batch_file_rename.py
@@ -9,17 +9,21 @@
 # Description			: This will batch rename a group of files in a given directory, once you pass the current and new extensions
 
 import os															# Load the library module
-import sys															# Load the library module
+from sys import argv                            # imports argv from sys to take arguments given in the command line when the program is initiated
 
-work_dir=sys.argv[1]											# Set the variable work_dir with the first argument passed
-old_ext=sys.argv[2]											# Set the variable work_dir with the first argument passed
-new_ext=sys.argv[3]											# Set the variable work_dir with the first argument passed
+work_dir, old_ext, new_ext = argv[1:]       # work_dir is the work directory, old_ext and new_ext are the current and wanted file extentions respectively. 
 
 files = os.listdir(work_dir)									# Set the variable files, by listing everything in the directory 
 for filename in files:											# Loop through the files
   file_ext = os.path.splitext(filename)[1]				# Get the file extension
   if old_ext == file_ext:										# Start of the logic to check the file extensions, if old_ext = file_ext
     newfile = filename.replace(old_ext, new_ext)	# Set newfile to be the filename, replaced with the new extension
+    while os.path.isfile(newfile):                         # Check if the new file name already exists to prevent overwrite
+        num = 2                                             # a number to add to the file name
+        num_new_ext = "_" + str(num) + new_ext              # creates a new string to append to the end of file name
+        newfile = filename.replace(old_ext, num_new_ext)    # apply changes to the new file name
+        num += 1                                            # increment the number in case the name still exists
     os.rename(													# Write the files
 	    os.path.join(work_dir, filename),
-		os.path.join(work_dir, newfile))
\ No newline at end of file
+		os.path.join(work_dir, newfile))
+