def __verify_username(self, username):
if len(username) > self.__max_length or len(username) < <NUM_LIT:3>:<EOL><INDENT>raise ValueError(<EOL>f"<STR_LIT>"<EOL>)<EOL><DEDENT>if any(c not in string.ascii_letters + string.digits for c in username):<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>
Raises an exception if the given username is not valid.