import datetime
import pytz


def tzware_datetime():
    """
    Return a timezone aware datetime.

    :return: Datetime
    """
    return datetime.datetime.now(pytz.utc)


def timedelta_months(months, compare_date=None):
    """
    Return a new datetime with a month offset applied.

    :param months: Amount of months to offset
    :type months: int
    :param compare_date: Date to compare at
    :type compare_date: date
    :return: datetime
    """
    if compare_date is None:
        compare_date = datetime.date.today()

    delta = months * 365 / 12
    compare_date_with_delta = compare_date + datetime.timedelta(delta)

    return compare_date_with_delta


def format_date_to_excel(date):
    """ Format a local date for consumption by Excel
    """
    if not date:
        return ''
    return date.strftime('%Y-%m-%d %H:%M:%S')