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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 build_delta_t_table(delta_t_recent):
 """Build a table for interpolating Delta T. Given a 2xN array of recent Delta T values, whose element 0 is a sorted array of TT Julian dates and element 1 is Delta T values, this routine returns a more complete table by prepending two built-in data sources that ship with Skyfield as pre-built arrays: * The historical values from Morrison and Stephenson (2004) which the http://eclipse.gsfc.nasa.gov/SEcat5/deltat.html NASA web page presents in an HTML table. * The United States Naval Observatory ``historic_deltat.data`` values for Delta T over the years 1657 through 1984. """

    ancient = load_bundled_npy('morrison_stephenson_deltat.npy')
    historic = load_bundled_npy('historic_deltat.npy')

    # Prefer USNO over Morrison and Stephenson where they overlap.
    historic_start_time = historic[0,0]
    i = searchsorted(ancient[0], historic_start_time)
    bundled = concatenate([ancient[:,:i], historic], axis=1)

    # Let recent data replace everything else.
    recent_start_time = delta_t_recent[0,0]
    i = searchsorted(bundled[0], recent_start_time)
    row = ((0,),(0,))
    table = concatenate([row, bundled[:,:i], delta_t_recent, row], axis=1)

    # Create initial and final point to provide continuity with formula.
    century = 36524.0
    start = table[0,1] - century
    table[:,0] = start, delta_t_formula_morrison_and_stephenson_2004(start)
    end = table[0,-2] + century
    table[:,-1] = end, delta_t_formula_morrison_and_stephenson_2004(end)
    return table