helper for interval_range to check type compat of start/end/freq

def _is_type_compatible(a, b):
    """helper for interval_range to check type compat of start/end/freq"""
    is_ts_compat = lambda x: isinstance(x, (Timestamp, DateOffset))
    is_td_compat = lambda x: isinstance(x, (Timedelta, DateOffset))
    return ((is_number(a) and is_number(b)) or
            (is_ts_compat(a) and is_ts_compat(b)) or
            (is_td_compat(a) and is_td_compat(b)) or
            com._any_none(a, b))