Converts or localizes a time series to UTC.

    Parameters
    ----------
    time : datetime.datetime, pandas.DatetimeIndex,
           or pandas.Series/DataFrame with a DatetimeIndex.
    location : pvlib.Location object

    Returns
    -------
    pandas object localized to UTC.

def localize_to_utc(time, location):
    """
    Converts or localizes a time series to UTC.

    Parameters
    ----------
    time : datetime.datetime, pandas.DatetimeIndex,
           or pandas.Series/DataFrame with a DatetimeIndex.
    location : pvlib.Location object

    Returns
    -------
    pandas object localized to UTC.
    """
    if isinstance(time, dt.datetime):
        if time.tzinfo is None:
            time = pytz.timezone(location.tz).localize(time)
        time_utc = time.astimezone(pytz.utc)
    else:
        try:
            time_utc = time.tz_convert('UTC')
        except TypeError:
            time_utc = time.tz_localize(location.tz).tz_convert('UTC')

    return time_utc