what is the minimum surface area shape required in order to contain a 1 meter line at all angles

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been stuck on solving/proving the following puzzle:

You need to make a hole in the wall, so that a 1 meter line can pass it through the hole at all angels, find a shape with minimum surface area that would satisfy the above conditions ?

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Take an equilateral triangle with sides of length $1$, and then use each vertex as the center of a circular arc passing through the other two vertices:

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This is at least a contender, with area $3\cdot\frac{\pi}{6}-2\cdot\frac{\sqrt3}{4}$, less than a circle of diameter $1$ or a quarter-circle of radius $1$, which are other convex shapes meeting the description. This shape may be the winner if you require a convex shape, but I have no ideas for proving it.