Arduino to imitate a momentary switch

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LarryD:
Look at this:
digitalRead() - Arduino Reference

You would then use pin 13 to control:
Powerswitch tail 2 : ID 268 : Adafruit Industries, Unique & fun DIY electronics and kits

Thanks for this, but all I need to do is to be able to short two pins of a device that requires me to press the button.