This backdoor is python script, that opens a connection from a victim (reverse shell).
download_execute.py - is a python script that doanloads a vitrus to a victim machine.
listener.py - is a python script that listens connection from a victim on a selected port (ex. 4444) and establishes connection. Afterwards hacker can send commands to a victim.
win_listener.py - is a python script that can be converted to a virus through ex. pyinstaller. It can be masquerade to any file (ex. sample.pdf).