python中嵌套元组的元素操作

元组的元素添加非常简单：

a = (1,2,3,4)
b = (2,4,6,8)
tuple(x+y for x,y in zip(a,b))

(3,6,9,12)

但嵌套元组的元素级加法更为复杂：

a = ((1,2),(3,4),(5,6))
b = ((2,4),(6,8),(10,12))
tuple(x+y for tup_a, tup_b in zip(a,b) for x,y in zip(tup_a,tup_b))

(3,6,9,12,15,18)

元组是扁平的。如何在保留元组结构的同时对未使用的元组执行元素级加法

这是所需的输出：

((3,6),(9,12),(15,18))

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嵌套生成器表达式：

tuple(tuple(x + y for x, y in zip(tup_a, tup_b)) for tup_a, tup_b in zip(a, b))

演示：

这可能就是我要做的，这应该比两个层次更深入

>>> a = ((1,2),(3,4),(5,6))
>>> b = ((2,4),(6,8),(10,12))
>>> tuple(tuple(x + y for x, y in zip(tup_a, tup_b)) for tup_a, tup_b in zip(a, b))
((3, 6), (9, 12), (15, 18))

def xsum(a,b):
    if isinstance(a,(list,tuple)) and isinstance(b,(list,tuple)):
       return [xsum(x,y) for x,y in zip(a,b)]
    return a+b

a = ((1,2),(3,4),(5,6))
b = ((2,4),(6,8),(10,12))
print [xsum(x,y) for x,y in zip(a,b)]