def calculate_dt_utcoffset(datetime_aware):
    """
    Calculate the UTC offset for a specific dt object that is timezone-aware 
    (tzinfo already included).
    
    Parameters
    ----------
    datetime_in : datetime.datetime
        dt.datetime format time in the local desired timezone. (If the tzinfo='UTC',
        the offset will naturally be 0)
    
    Returns
    -------
    utc_offset : float
        Number of hours the supplied aware datetime object is offset from UTC
    
    Example
    -------  
    obs.calculate_dt_utcoffset( obs.dt_naive_to_dt_aware(dt.datetime.now(),'US/Eastern') )
    """
    utcoffset_delta=datetime_aware.utcoffset() #utcoffset() returns a dt.timedelta
    return utcoffset_delta.total_seconds()/3600.