Example AYON / OpenPype PreLaunchHook to insert Ayon's FFMPEG to PATH environment variable on launch of applications

ayon_insert_ffmpeg_path_prelaunchhook.py

import os
from openpype.lib.applications import PreLaunchHook, LaunchTypes
from openpype.lib.vendor_bin_utils import get_ffmpeg_tool_path

class AddFFMPEGToPath(PreLaunchHook):
    """Insert Ayon FFMPEG in `PATH`"""

    # Should be as last hook because must change launch arguments to string
    app_groups = {"*"}
    platforms = {"*"}
    launch_types = {LaunchTypes.local}

    def execute(self):
    
        path = self.launch_context.env.get("PATH")
        
        ffmpeg = get_ffmpeg_tool_path()
        ffmpeg_bin = os.path.dirname(ffmpeg)
        
        if path:
            path = os.pathsep.join([ffmpeg_bin, path])
        else:
            path = ffmpeg_bin

        self.launch_context.env["PATH"] = path

Based on AYON discord discussion here