Conky setup for sessional data usage

As in the above picture, the integration for data usage is acheived by the following code

    ${color orange}${voffset 2}${hr 1}
    ${color1}Network using vnStat "-i", "-w" and "-m"
    ${color}${goto 5}Today ${goto 100}Yesterday ${goto 225}Week ${goto 325}Month ${color 
    green}
    ${execi 300 vnstat -i eth0 | grep "today" | awk '{print $8" "substr ($9, 1, 1)}'} ${goto 
    110}${execi 300 vnstat -i eth0 | grep "yesterday" | awk '{print $8" "substr ($9, 1, 
    1)}'} ${goto 220}${execi 300 vnstat -i eth0 -w | grep "current week" | awk '{print $9" 
    "substr ($10, 1, 1)}'} ${goto 315}${execi 300 vnstat -i eth0 -m | grep "`date +"%b 
    '%y"`" | awk '{print $9" "substr ($10, 1, 1)}'}
    ${color orange}${voffset 2}${hr 1}

refernce-https://askubuntu.com/questions/1459/how-can-you-monitor-total-internet-data-usage-across-reboots

now what i want to do is to replace one of the perimeter to " session" data usage so that i can monitor in realtime, the amount of data i m consuming in my current session

so far i can only use

vnstat -l 1 -i wlp3s0

to monitor live sessional data from my network (on terminal).. can anyone help me integrate this code into conky? Thanks.