implement code

i have a fully rigged avatar. My project is about Sign language. Can someone give me a head start like how to implement python in such a way that whenever a sentence is written my avatar performs the required gesture.

Do you already have the animations/gestures?
Are you just trying to link your animations to user inputs?
I would recommend making simple animations for each one of your gestures, if you have not already, and then follow the bpy documentation on how to call & select animation actions. I know off the top of my head that:
bpy.ops.screen.animation_play() will play the selected animation
bpy.ops.screen.animation_cancel() will stop the animation
If you are at this point already then maybe you can write out some sort of case statements in python (after going through the user input), applies the appropriate animations when a key word is found.