Zero fill all files ends with .secrete using python3

fillZero.py

#!/usr/bin/env python

# Tested in:
# Windows 8.1 Enterprise, en_US
# Python 3.4.2 (v3.4.2:ab2c023a9432, Oct  6 2014, 22:15:05)
#              [MSC v.1600 32 bit (Intel)] on win32

import os
import sys


def fillZero(filename):
    print(filename)
    zeros = '\0' * os.path.getsize(filename)
    with open(filename, 'w') as f:
        f.write(zeros)
        print('---> filled with {} zeros!'.format(os.path.getsize(filename)))

if __name__ == '__main__':
    # print(str(sys.argv))
    if len(sys.argv) > 1:
        # for fileName in sys.argv[1:]:
        #     fillZero(fileName)
        print('Executing the program({}) with extra arguments is not tested.'
              .format(str(sys.argv[0])))
        print('Feel free to fork it and complete it.')
    else:
        # print(str(sys.argv[0]), "<file1> <file2> ...")
        try:
            ends = '.secrete'
            print('Zero fill all files ends with', ends)
            for fileName in os.listdir("./"):
                if fileName.endswith(ends):
                    fillZero('./' + fileName)
            print('Done!')
        except UnicodeEncodeError:
            print('UnicodeEncodeError!',
                  'Run `chcp 65001` in this CMD and try again.')

For convenience, you can create a fillZero.bat file and fill it with:

chcp 65001
fillZero.py
pause