#12a
a=3
if a<4:
    try:
        b=a/(a-3)
        print(b)

    except ZeroDivisionError:
        print("Exception ======",ZeroDivisionError)

#12b

try:
    a = [1,2,3,4,5]
    print(a[5])
except LookupError:
    print("Index out of bound error.")
else:
    print("Success")