title: selenium webdriver.firefox() Error
body: <p>I am trying to use selenium to start google chrome but i get an error
  here is my code:</p>
  
  <pre><code>from selenium import webdriver
  browser = webdriver.Firefox()
  browser.get('http://localhost:8000')
  assert 'Django' in browser.title
  </code></pre>
  
  <p>here is the error:</p>
  
  <pre><code>Traceback (most recent call last):
  File "functional_tests.py", line 5, in &lt;module&gt;
  browser = webdriver.Firefox(firefox_binary=binary)
  File "C:\Python27\lib\site-
  packages\selenium\webdriver\firefox\webdriver.py", line 140, in __init__
  self.service.start()
  File "C:\Python27\lib\site-packages\selenium\webdriver\common\service.py", line 81, in start
  os.path.basename(self.path), self.start_error_message)
  selenium.common.exceptions.WebDriverException: Message: 'geckodriver' executable needs to be in PATH.
  
   Exception AttributeError: "'Service' object has no attribute 'process'" in &lt;bound method Service.__del__ of &lt;selenium.webdriver.firefox.service.Service object at 0x03D51FD0&gt;&gt; ignored
  </code></pre>
  
  <p>any help with that?</p>