# 导入数学库import math# 检查某些值是否为非数字 (NaN)print(math.isnan(56))print(math.isnan(-45.34))print(math.isnan(+45.34))print(math.isnan(math.inf))print(math.isnan(float("nan")))print(math.isnan(float("inf")))print(math.isnan(float("-inf")))print(math.isnan(math.nan))