def countdown(self, interval: float = <NUM_LIT:0.5>):
for c in '<STR_LIT>':<EOL><INDENT>self.char_on(c)<EOL>time.sleep(interval * <NUM_LIT>)<EOL>self.all_off()<EOL>time.sleep(interval * <NUM_LIT>)<EOL><DEDENT>
Display a numeric countdown from 5
:param interval: The interval in seconds for each number.