python ask for real values until negative value diplay highest and lowest

1print "Enter numbers, stops when negative value is entered:"
2nums = []
3while True: # infinite loop
4    try: n = int(raw_input("Enter a number: ")) # raw_input returns a string, so convert to an integer
5    except ValueError: 
6        n = -1
7        print "Not a number!"
8    if n < 0: break # when n is negative, break out of the loop
9    else: nums.append(n)
10print "Maximum number: {}".format(max(nums))