help with this function please. explanation if possible. thank you!

recursion to perform the bitwise, "elementary-school" addition algorithm that we discussed in lecture, and it should return the result. It must not perform any base conversions. Your function should add one pair of bits at a time, working from right to left and including any necessary "carry" bits, as discussed in lecture. For example, when adding 101110 and 100111 , you end up with 3 carry bits, as shown in blue below: Notes/hints: - Base cases: Because the function will be called recursively on smaller and smaller strings, you will eventually get down to an empty string for one or both of the inputs. If either of the strings (b1 or b2) is the empty string, your function should return the other string. - Handling cases that require a carry bit can be the most difficilit part of this problem. The trick is to call the function recursively a second time to add in the carry bit! We discussed this in lecture. - Here are some test cases: >>> add_bitwise('11', '100') result: '111' >>> add_bitwise('11', '1') result: '100