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from what I've seen they are all different...
is it common anode or cathod?
first, us your dmm to find the 2 pins that are common (use continuity meter on dmm)
second, you "should" be able to use your dmm on the diode test feature and put the common (black) lead on one of the 2 common pins, put the red lead on any one of the other pins. If it is common cathode, one of the segments on the LED should light up... now you will know what each pin does.
if it is common anode, do the same thing, but put the red lead one of the common pins, and use the black lead to touch any/all of the other pins.
in some cases, the dmm might not provide enough juice to turn on the led... in this case you can put 5 volts through a 330ohm resistor and connect the positive(red) and negative(black) leads as stated above...