KATY PERRY ? UR SO GAY
I?m pretty sure this is right cuz I watched her playing it live...
LIVE VIDEO:  


e|-------0-----------0------------0-----------0----------------------|
B|-------0-----------0------------1-----------0----------------------|
G|-------0-----------0------------2-----------0----------------------|
D|-------5-----------2------------2-----------1----------------------|
A|-------7-----------3------------0-----------2----------------------|
E|-------7-----------3------------0-----------2----------------------|
Thats basically it... thats what Katy plays throughout the entire song

GUITAR 2 - this is the short part the second guitar plays when it is live. But if ur 
use the recorded version, u would have to play along to the whistles(i dont think its the 
though)....

GUITAR 2 (INTRO WHISTLES)
e|------------------------------------------------------------------------|
B|-------------12----------------------------------10-12------------------|
G|-----9--12--------------------9-9-9-9--12-12-12-------------------------|
D|--9-------------10-10-10-10---------------------------------------------|
A|------------------------------------------------------------------------|
E|------------------------------------------------------------------------|

e|-------------------------------------------------------------------------|
B|---------------------------------10-12----12h13p12----7h8p7-----8--------|
G|----------------9-9-9-9-12-12-12--------------------------------9--------|
D|---10-10-10-10--------------------------------------------------9--------|
A|----------------------------------------------------------------7--------|
E|-------------------------------------------------------------------------|
*strum from the bottom to the top on the last note!