Calculadora de Desplazamiento de Zona Horaria

from datetime import datetime
import zoneinfo  # Python 3.9+

def get_offset_hours(tz_name: str, dt: datetime) -> float:
    tz = zoneinfo.ZoneInfo(tz_name)
    aware = dt.replace(tzinfo=zoneinfo.ZoneInfo("UTC")).astimezone(tz)
    offset = aware.utcoffset()
    return offset.total_seconds() / 3600

def timezone_diff(from_tz: str, to_tz: str, date_str: str = None) -> float:
    if date_str:
        dt = datetime.fromisoformat(date_str + "T12:00:00")
    else:
        dt = datetime.utcnow()
    from_offset = get_offset_hours(from_tz, dt)
    to_offset   = get_offset_hours(to_tz,   dt)
    return to_offset - from_offset

diff = timezone_diff("America/New_York", "Asia/Tokyo", "2025-06-15")
print(f"Tokyo is {diff:+.1f}h from New York on 2025-06-15")