as seen from https://github.com/gscales/Powershell-Scripts/blob/5ef520c12f139609c50f87354a617a7ab750fbb1/Get-M365TenantAudienceMetadata.ps1

Get-M365TenantAudienceMetadata.py

#!/usr/bin/env python3
import sys
import requests

tenant = (
    sys.argv[1]
    if len(sys.argv) > 1
    else sys.exit(f"usage: {sys.argv[0]} <tenant_id or domain>")
)

try:
    url = f"https://accounts.accesscontrol.windows.net/{tenant}/metadata/json/1"
    metadata = requests.get(url, timeout=30).json()
    realm = metadata.get("realm", tenant)

    if tenant != realm:
        print(f"tenant: {realm}\n")

    domains = set()
    for entry in metadata.get("allowedAudiences", []):
        domain = entry.split("@")[-1]
        if "." in domain:
            domains.add(domain)

    for domain in domains:
        print(domain)

except Exception as e:
    sys.exit(f"error: {e}")