The solution that selenium3 can't open Firefox browser
The version of Firefox I installed is 45.0.2
Inspection method:
Check the webdriver.py in C:\ Python27\ Lib\ site-packages\ selenium\ webdriver\ firefox. In the def_init_ function, executable_path= "geckodriver". The environment you built earlier is executable_path= "wires".
Selenium3.x versions all use geckodriver to drive firefox
Download address: https://github.com/mozilla/geckodriver/releases
Put it in the root directory of the Python installation, for example: d:\ Python36
