Four identical light rigid rods are connected by frictionless joints in the shape of a square. A light spring with a force constant k connects two opposite vertices of the square. A small mass m is attached to one of the joints as shown.

The assembly is placed on a horizontal frictionless table and attached to the table at point A. Mass m is then pulled horizontally a small distance directly away from A and then released. How long would it take the mass to come back to its original position for the first time?

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