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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 extract_gti_data(hdu_in):
 """ Extract some GTI related data Parameters ------- hdu_in : `astropy.io.fits.BinTableHDU` The GTI data Returns ------- data : `astropy.io.fits.BinTableHDU` data exposure : float Exposure value taken from FITS header tstop : float TSTOP value taken from FITS header """

    data = hdu_in.data
    exposure = hdu_in.header['EXPOSURE']
    tstop = hdu_in.header['TSTOP']
    return (data, exposure, tstop)