rec.array([(datetime.datetime(2012, 1, 1, 1, 1), 2.0999999046325684), (
    datetime.datetime(2012, 1, 1, 1, 2), -3.0999999046325684), (datetime.
    datetime(2012, 1, 1, 1, 3), 0.10000000149011612)], dtype=[('timestamp',
    '|O8'), ('x', '<f4')])
How to make a numpy recarray with datatypes (datetime,float)?