How to Get the Timeline Start Frame with the DaVinci Resolve API

import os
import sys
from pathlib import Path


def import_resolve_module():
    try:
        import DaVinciResolveScript as dvr
        return dvr
    except ImportError:
        search_paths = [
            os.environ.get("RESOLVE_SCRIPT_API", ""),
            os.environ.get("RESOLVE_MODULES", ""),
            r"C:\\ProgramData\\Blackmagic Design\\DaVinci Resolve\\Support\\Developer\\Scripting\\Modules",
            "/opt/resolve/Developer/Scripting/Modules",
            "/opt/BlackmagicDesign/DaVinciResolve/Developer/Scripting/Modules",
            "/Library/Application Support/Blackmagic Design/DaVinci Resolve/Developer/Scripting/Modules",
            str(Path.home() / "Library/Application Support/Blackmagic Design/DaVinci Resolve/Developer/Scripting/Modules"),
        ]
        for path in search_paths:
            if path and os.path.isdir(path) and path not in sys.path:
                sys.path.append(path)
        import DaVinciResolveScript as dvr
        return dvr


def safe_call(obj, name, *args, **kwargs):
    try:
        fn = getattr(obj, name, None)
        if callable(fn):
            return fn(*args, **kwargs)
    except Exception:
        return None
    return None


def get_project_and_timeline():
    dvr = import_resolve_module()
    resolve = dvr.scriptapp("Resolve")
    if not resolve:
        raise RuntimeError("DaVinci Resolve API is unavailable")

    project_manager = resolve.GetProjectManager()
    project = project_manager.GetCurrentProject() if project_manager else None
    if not project:
        raise RuntimeError("No DaVinci Resolve project is open")

    timeline = project.GetCurrentTimeline()
    if not timeline:
        raise RuntimeError("No active Timeline")

    return resolve, project, timeline


def get_timeline_base_frame(timeline) -> int:
    get_start_frame = getattr(timeline, "GetStartFrame", None)
    if callable(get_start_frame):
        value = safe_call(timeline, "GetStartFrame")
        if value is not None:
            return int(value)

    value = safe_call(timeline, "GetStart")
    if value is not None:
        return int(value)

    return 0


resolve, project, timeline = get_project_and_timeline()
base_frame = get_timeline_base_frame(timeline)
print("Timeline base frame:", base_frame)