Quite a number of my fellow teachers have been saying that we should NEVER use breaks in loops. However in our examination there is often a need to validate an input e.g.

while True:
    ID = input("What is the cow's ID code?")
    if len(ID) == 3:
        CowID.append(ID)
        break
    else:
        print("Cow ID has been entered wrongly.")

The break works perfectly well in Python, but it has been suggested to me that I avoid using such constructs. What are your thoughts on this and does anyone have credible sources one way or another? In the age of the Internet my students will quickly find break and I would need a very strong argument as to why they don't use it. Equally, if I go against these other teachers I will need credible evidence as to why I am doing it this way.

Your thoughts, arguments and ideas are very much appreciated. This debate has been rumbling on already for over a month and I would like to get a good answer before I plan next year's lessons.