Set Python Environment and Execute Python Code in PHP Script

I am trying to convert the vcd file to wavedrom json file using the python library

https://github.com/Toroid-io/vcd2wavedrom

when I run on my terminal the below code works fine

 source /var/www/xxx/vcd2wavedrom/verilog-env/bin/activate && 
 python3 /var/www/xxx/vcd2wavedrom/vcd2wavedrom/vcd2wavedrom.py 
 -i /var/www/xxx/uuids/abcd/dump.vcd 
 -o /var/www/xxx/uuids/abcd/dump.json

When i execute the same code in my php script as

$env = 'source /var/www/xxx/vcd2wavedrom/verilog-env/bin/activate';

cmd = "python3 /var/www/xxx/vcd2wavedrom/vcd2wavedrom/vcd2wavedrom.py -i ".$uuid_dir."/dump.vcd -o ".$uuid_dir."/dump.json";

#!/bin/sh

shell_exec($env ." && ". $cmd);

I am getting sh: 1: source: not found error.

How can set the venv from php script.

I am not a python developer. Please elaborate your answer as much as possible for me to understand better.

I tried to remove the source, but I got

 sh: 1: /var/www/xxx/vcd2wavedrom/verilog-env/bin/activate: Permission denied
 Traceback (most recent call last):
 File "/var/www/xxx/vcd2wavedrom/vcd2wavedrom/vcd2wavedrom.py", line 9, in <module>
 from vcdvcd.vcdvcd import VCDVCD
 ModuleNotFoundError: No module named 'vcdvcd'

I set verilog-env folder to 777 but still the same error persists