### dji_imah_fwsig.py

DJI Firmware IMaH Un-signer and Decryptor tool; allows to decrypt and un-sign module
from `.sig` file which starts with `IM*H`. Use this tool after untarring single
modules from a firmware package, to decrypt its content. The tool can also re-sign
a module, as long as private part of the chosen key is available.

Keys used for encryption and authentication were changing over time; when an
`IM*H` file refers to a key for which the tool has several versions, it will
display a list of possible keys in a warning message, and select the most
recent key for current operation.

Example of un-signing Camera firmware for *Mavic Pro*: