python unsupported operand type(s) for -: 'list' and 'list'

这个报错通常会在两个列表相减时出现，因为列表之间不能直接做减法。你可以通过使用列表推导式或循环来逐个计算列表元素之间的差值。例如：

a = [1, 2, 3]
b = [3, 2, 1]
c = [a[i] - b[i] for i in range(len(a))] # c = [-2, 0, 2]

或者：

a = [1, 2, 3]
b = [3, 2, 1]
c = []
for i in range(len(a)):
c.append(a[i] - b[i])
# c = [-2, 0, 2]