Given two queues, q1 and q2, where a background process copies elements from q1 to q2, write an error handling function to copy elements from q2 back to q1 if an error occurs. Use the following functions: q_len(), q_insert(qname), and q_remove(qname, data). q_len() returns an integer. The return types of the other functions are unknown. The data type in the queues is also unknown.