def get_hounsfield_coeffs(ds_open_file):
    """Returns the slope-intercept pair needed to convert an image
    to Hounsfield units"""
    rescale_slope = ds_open_file[0x28, 0x1053].value
    rescale_intercept = ds_open_file[0x28,0x1052].value

    return (rescale_slope,rescale_intercept)