Does anyone know how to use python-qrtools with the Raspberry pi official camera to decode qr codes?

Hi, I want to connect a usb device that requires a lot of power from th RPi, like a 3g modem. Is it ok to plug a USB Y cable for it (like this one http://www.ebay.com/itm/PCD-USB-Y-Cable-Splitter-YC150B-US-SELLER-3-Extension-Cord-1-Female-2-Male-/221022644917?pt=PDA_Accessories&hash=item3375f9eab5)?...

Thank you!!
At first, I thought an error BIOS message would show up.

Hi,
just plugging the power cable and HDMI to the tv... should anything be displayed on the tv at all?
no sd card, no keyboard. just power and HMDI cables.

thank you