You got a lot of good advice above so I'm just going to rant instead....
Thanks to ignorant media hype and THE PETA Planet network, the average uneducated person hears "python" and thinks of a 20 foot killer snake that regularly feed on large game like deer or alligator, and when given the chance small children.
Thanks to this your timid little friend is viewed as a dangerous animal.
Positive side of this - they didn't say no, and are willing to work with you, and that its just a letter not dangerous animal insurance.