How do I hook up a psu to power an xbee?


I can’t find an answer to this anywhere so I assume it’s either really simple or really complex.

I want to power an xbee series 2 through the (uk) mains power (without an arduino etc). I need the xbee to be constantly vigilant for 2 weeks so I don’t think batteries and sleep modes will do it.

Although I’m learning fast I’m relatively new to electronics so I’m unsure what it takes to put a psu into the circuit. I’ve seen that voltage regulators should be used but is it just a case of using a 3v psu, a barrel socket and a 3.3v(?) voltage regulator hooked up to the xbee? This seems far too simple and I’m a little cautious to experiment with the mains supply for obvious reasons. Any help in simple language would be very much appreciated.

Many thanks