Spins up a new web browser and returns the driver.
    Can also be used to spin up additional browsers for the same test.

def get_local_driver(
        browser_name, headless, proxy_string, proxy_auth,
        proxy_user, proxy_pass, user_agent, disable_csp):
    '''
    Spins up a new web browser and returns the driver.
    Can also be used to spin up additional browsers for the same test.
    '''
    downloads_path = download_helper.get_downloads_folder()
    download_helper.reset_downloads_folder()

    if browser_name == constants.Browser.FIREFOX:
        try:
            try:
                # Use Geckodriver for Firefox if it's on the PATH
                profile = _create_firefox_profile(
                    downloads_path, proxy_string, user_agent, disable_csp)
                firefox_capabilities = DesiredCapabilities.FIREFOX.copy()
                firefox_capabilities['marionette'] = True
                options = webdriver.FirefoxOptions()
                if headless:
                    options.add_argument('-headless')
                if LOCAL_GECKODRIVER and os.path.exists(LOCAL_GECKODRIVER):
                    make_driver_executable_if_not(LOCAL_GECKODRIVER)
                    firefox_driver = webdriver.Firefox(
                        firefox_profile=profile,
                        capabilities=firefox_capabilities,
                        options=options,
                        executable_path=LOCAL_GECKODRIVER)
                else:
                    firefox_driver = webdriver.Firefox(
                        firefox_profile=profile,
                        capabilities=firefox_capabilities,
                        options=options)
            except WebDriverException:
                # Don't use Geckodriver: Only works for old versions of Firefox
                profile = _create_firefox_profile(
                    downloads_path, proxy_string, user_agent, disable_csp)
                firefox_capabilities = DesiredCapabilities.FIREFOX.copy()
                firefox_capabilities['marionette'] = False
                firefox_driver = webdriver.Firefox(
                    firefox_profile=profile, capabilities=firefox_capabilities)
            return firefox_driver
        except Exception as e:
            if headless:
                raise Exception(e)
            return webdriver.Firefox()
    elif browser_name == constants.Browser.INTERNET_EXPLORER:
        if not IS_WINDOWS:
            raise Exception(
                "IE Browser is for Windows-based operating systems only!")
        from selenium.webdriver.ie.options import Options
        ie_options = Options()
        ie_options.ignore_protected_mode_settings = False
        ie_options.ignore_zoom_level = True
        ie_options.require_window_focus = False
        ie_options.native_events = True
        ie_options.full_page_screenshot = True
        ie_options.persistent_hover = True
        ie_capabilities = ie_options.to_capabilities()
        if LOCAL_IEDRIVER and os.path.exists(LOCAL_IEDRIVER):
            make_driver_executable_if_not(LOCAL_IEDRIVER)
            return webdriver.Ie(
                capabilities=ie_capabilities,
                executable_path=LOCAL_IEDRIVER)
        else:
            return webdriver.Ie(capabilities=ie_capabilities)
    elif browser_name == constants.Browser.EDGE:
        if not IS_WINDOWS:
            raise Exception(
                "Edge Browser is for Windows-based operating systems only!")
        edge_capabilities = DesiredCapabilities.EDGE.copy()
        if LOCAL_EDGEDRIVER and os.path.exists(LOCAL_EDGEDRIVER):
            make_driver_executable_if_not(LOCAL_EDGEDRIVER)
            return webdriver.Edge(
                capabilities=edge_capabilities,
                executable_path=LOCAL_EDGEDRIVER)
        else:
            return webdriver.Edge(capabilities=edge_capabilities)
    elif browser_name == constants.Browser.SAFARI:
        return webdriver.Safari()
    elif browser_name == constants.Browser.OPERA:
        if LOCAL_OPERADRIVER and os.path.exists(LOCAL_OPERADRIVER):
            make_driver_executable_if_not(LOCAL_OPERADRIVER)
            return webdriver.Opera(executable_path=LOCAL_OPERADRIVER)
        else:
            return webdriver.Opera()
    elif browser_name == constants.Browser.PHANTOM_JS:
        with warnings.catch_warnings():
            # Ignore "PhantomJS has been deprecated" UserWarning
            warnings.simplefilter("ignore", category=UserWarning)
            return webdriver.PhantomJS()
    elif browser_name == constants.Browser.GOOGLE_CHROME:
        try:
            chrome_options = _set_chrome_options(
                downloads_path, headless, proxy_string, proxy_auth,
                proxy_user, proxy_pass, user_agent, disable_csp)
            if headless:
                # Headless Chrome doesn't support extensions, which are
                # required when using a proxy server that has authentication.
                # Instead, base_case.py will use PyVirtualDisplay when not
                # using Chrome's built-in headless mode. See link for details:
                # https://bugs.chromium.org/p/chromium/issues/detail?id=706008
                if not proxy_auth:
                    chrome_options.add_argument("--headless")
                chrome_options.add_argument("--disable-gpu")
                chrome_options.add_argument("--no-sandbox")
            if LOCAL_CHROMEDRIVER and os.path.exists(LOCAL_CHROMEDRIVER):
                make_driver_executable_if_not(LOCAL_CHROMEDRIVER)
                return webdriver.Chrome(
                    executable_path=LOCAL_CHROMEDRIVER, options=chrome_options)
            else:
                return webdriver.Chrome(options=chrome_options)
        except Exception as e:
            if headless:
                raise Exception(e)
            if LOCAL_CHROMEDRIVER and os.path.exists(LOCAL_CHROMEDRIVER):
                make_driver_executable_if_not(LOCAL_CHROMEDRIVER)
                return webdriver.Chrome(executable_path=LOCAL_CHROMEDRIVER)
            else:
                return webdriver.Chrome()
    else:
        raise Exception(
            "%s is not a valid browser option for this system!" % browser_name)