Are there any good material for network module development ?

Hello, All

I’m network engineer. and I am developing ansible network module.

I must develope network module by using telnet connection (not ssh) becuase of my customer uses old and unknown vendor devices

Already, what i want is developed in Ansible version 2.2.3.0 )

But, network module in version 2.3 is changed so much.

Are there any good material for network module development ?