<p>Using <a href="http://pyobjc.sourceforge.net/" rel="noreferrer">PyObjC</a>, you can use Python to write Cocoa applications for OS X. Can I write native iPhone apps using Python and if so, how?</p>

Not currently, currently the only languages available to access the iPhone SDK are C/C++, Objective C and Swift.
There is no technical reason why this could not change in the future but I wouldn't hold your breath for this happening in the short term.
That said, Objective-C and Swift really are not too scary...
2016 edit
Javascript with NativeScript framework is available to use now.