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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 resize_psf(psf, input_pixel_scale, output_pixel_scale, order=3):
 """ Resize a PSF using spline interpolation of the requested order. Parameters psf : 2D `~numpy.ndarray` The 2D data array of the PSF. input_pixel_scale : float The pixel scale of the input ``psf``. The units must match ``output_pixel_scale``. output_pixel_scale : float The pixel scale of the output ``psf``. The units must match ``input_pixel_scale``. order : float, optional The order of the spline interpolation (0-5). The default is 3. Returns ------- result : 2D `~numpy.ndarray` The resampled/interpolated 2D data array. """


    from scipy.ndimage import zoom

    ratio = input_pixel_scale / output_pixel_scale
    return zoom(psf, ratio, order=order) / ratio**2