Method: This function will help to determine if provided slug is a valid bsf product or not, This way we will maintain consistency through out all our products.

Method: This function updates value of referer and product in option bsf_product_referer in form of key value pair as ‘product’ => ‘referer’

Method: This function will add utm_args to pro link or purchase link added utm_source by default additional utm_args such as utm_medium etc can be provided to generate location specific links