instaBrute Help Pleazzzze

i have kali linux 2.0 python2.7 and selenium 3

i get this massege

anyone have idea about it

python instaBrute.py -f usernames.txt -d dictionary.txt

Using 1 seconds of delay

Traceback (most recent call last):

File "instaBrute.py", line 142, in

main()

File "instaBrute.py", line 132, in main

driver = webdriver.Firefox(profile)

File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/firefox/webdriver.py", line 135, in _init_

self.service.start()

File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/common/service.py", line 71, in start

os.path.basename(self.path), self.starterrormessage)

selenium.common.exceptions.WebDriverException: Message: 'geckodriver' executable needs to be in PATH.

Exception AttributeError: "'Service' object has no attribute 'process'" in > ignored