def main_loop():
    try:
        test()
        a = 1 / 0
    except BaseException as error:
        file = open('test_log_file.txt', 'w')
        file.write(str(error))
        file.close()

 File "C:\Users\Admin\Desktop\test_module.py", line 9, in <module>
    main_loop()
File "C:\Users\Admin\Desktop\test_module.py", line 7, in main_loop
    a = 1 / 0
ZeroDivisionError: division by zero

python myscript.py 2>mylog.txt

 import traceback
try:
   1 / 0
except Exception:
    with open('errors.log', 'a') as f:
        f.write('{}\n'.format(traceback.format_exc())