How can I set a value error exception in python

Question

I have the following code:

while True:
            try:
                HOST = input(float(('Enter host IP'))
            except ValueError:
                print('Error. That is not a valid IP address.')
                continue

I require the user to input an IP address. I wanted to set an error so that if he uses a letter he gets an error. How can I do that and why isn't my code working?

Answer 1

Try something like this

while True:
    try:
        HOST = input('Enter host IP: ')
        if len(HOST.split(".")) != 4:
            raise ValueError
        for char in HOST:
            if char not in "0123456789.":
                raise ValueError
    except ValueError:
        print('Error. That is not a valid IP address.')
        continue
    else:
        break