How did burmese python get in America?

I assume you're talking about the Python 'problem' in areas such as Florida in the US.

The simple answer is - Burmese Pythons might look cute as a hatchling of around 30 inches, BUT - they grow BIG fairly quickly. Add to that - that they are also unpredictable snakes - and you begin to see the 'problem'. In all the years I have kept reptiles - only one specimen turned nasty. Wouldn't let me handle him - ever. Every hatchling I've had - grew to around eight feet by the time it was a year old !

The problem in america is simply unscrupulous owners ! They buy a 'little guy' as a new 'hobby'.... then, when the snake gets too big to handle - or it tries to eat the pet cat or dog - they simply release them into the wild ! The sensible thing to do with any 'unwanted' animal - is to re-home it with someone who actually knows the species - not just turn it loose !