def __init__(self, browser='ff', browser_version=None, os_name=None):
    'Constructor for the Driver factory'
    self.browser = browser
    self.browser_version = browser_version
    self.os_name = os_name
Constructor for the Driver factory
def __init__(self, browser='ff', browser_version=None, os_name=None):
    
    self.browser = browser
    self.browser_version = browser_version
    self.os_name = os_name