My 3 year old daughter locked the bathroom door from the inside....how do i open the door?

there is a hole in the front of the doorknob...im assuming the hole is for just such a situaton....i put a bobby pin into the hole but i cant figure out what im supposed to be doing
Update: it is a twist to lock on the inside and no screws to take off the door knob on the outside...I tried pushing the coat hanger in and i cant get it to work either
Update 2: hmmm...seems like it might be a screw to turn on the inside like was suggested...ill try to find a miniture screwdriver
Update 3: Awesome!! That was it and she is out! I was really getting frustrated there for a minute...Thanks Yahoo Answers!!! Especially Dan the Man and J-match....
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