Python两个列表交错合并方法

现有两个列表a,b,需要交错插入并合并成一个列表
a = [1, 2, 3]
b = [4, 5, 6]
目标：[1, 4, 2, 5, 3, 6]

#导入 chain
from itertools import chain
a = [1, 2, 3]
b = [4, 5, 6]
c=list(chain.from_iterable(zip(a, b)))
print(c)

#结果
[1, 4, 2, 5, 3, 6]