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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def parse_deltat_preds(fileobj):
 """Parse the United States Naval Observatory ``deltat.preds`` file. The old format supplies a floating point year, the value of Delta T, and one or two other fields:: 2015.75 67.97 0.210 0.02 The new format adds a modified Julian day as the first field: 58484.000 2019.00 69.34 -0.152 0.117 This function returns a 2xN array of raw Julian dates and matching Delta T values. """

    lines = iter(fileobj)
    header = next(lines)

    if header.startswith(b'YEAR'):
        # Format in use until 2019 February
        next(lines)             # discard blank line
        year_float, delta_t = np.loadtxt(lines, usecols=[0, 1]).T
    else:
        # Format in use since 2019 February
        year_float, delta_t = np.loadtxt(lines, usecols=[1, 2]).T

    year = year_float.astype(int)
    month = 1 + (year_float * 12.0).astype(int) % 12
    expiration_date = date(year[0] + 2, month[0], 1)
    data = np.array((julian_date(year, month, 1), delta_t))
    return expiration_date, data