box in box by recursive

h="."
b=[h]
w=1
exec'm=h+"  "*w;p=[w/2*h*-~w+h]+[w/2*m+h]*w;b=[x+y+x[::-1]for x,y in zip(([h*-~w]+[m]*w)*9,p+b+p[::-1])];w+=2;'*4
print("\n".join(b)).replace(".","[]")

Note that non-ascii characters in the above source code will be escaped (such as \x9f).

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