Selenium docs error using Firefox

Question

I’m new to programming world and started to learn python.

As part of my project I need to open, feed a webform and download an image and as I have to do this umpteen time, I looked around if there is any way to automate it using Python. While running Selenium example code as given here Selenium docs example code

Below is the error:

 driver = webdriver.Firefox()

  File "/usr/lib/python2.7/dist-packages/selenium/webdriver/firefox/webdriver.py", line 51, in __init__

    self.binary, timeout),

  File "/usr/lib/python2.7/dist-packages/selenium/webdriver/firefox/extension_connection.py", line 47, in __init__

    self.binary.launch_browser(self.profile)

  File "/usr/lib/python2.7/dist-packages/selenium/webdriver/firefox/firefox_binary.py", line 44, in launch_browser

    self._wait_until_connectable()

  File "/usr/lib/python2.7/dist-packages/selenium/webdriver/firefox/firefox_binary.py", line 81, in _wait_until_connectable

    self._get_firefox_output())

selenium.common.exceptions.WebDriverException: Message: 'The browser appears to have exited before we could connect.

I am using python 2.7.6 and the Firefox version is 40.0.3. Please help me to fix this.Thanks