else仅当你的while条件为假时才执行该子句。如果你break超出循环范围，或者引发了异常，则不会执行该异常。
考虑它的一种方法是关于条件的
if / else构造：
if condition: handle_true()else: handle_false()与循环构造类似：while condition: handle_true()else: # condition is false now, handle and go on with the rest of the program handle_false()
一个示例可能类似于：
while value < threshold: if not process_acceptable_value(value): # something went wrong, exit the loop; don't pass go, don't collect 200 break value = update(value)else: # value >= threshold; pass go, collect 200 handle_threshold_reached()
