auth.py

def concat_while(s0, s1):
    """
    Concatenate s0 and s1 with a space if the length of that concatenation
    is less than or equal to 30 characters. Otherwise it just returns s0.

    """
    if len(s0) > 30:
        return s0[:30]

    new = ' '.join([s0, s1])
    if len(new) > 30:
        return s0

    return new

def truncate_name(name):
    """
    Truncate a user's name to ensure that the length constraint on the
    first_name and last_name fields on the auth_user table are conformed
    to.

    """

    if ' ' in name:
        name = reduce(concat_while, name.split())
    else:
        name = name[:30]

    return name