numpy - Python troubles - Stack Overflow

I've been trying to throw together a python program that will align, crop and create an RGB image from HST and VLA .fits data. Unfortunately I've run into a bit of a problem with it continually opening a past file that does not exist in the folder and neither is it opening in the code itself. I've googled and googled and haven't found anything like it, so perhaps it's just common sense to most, but I can't figure it out. Here's the error message:

You can see at the top that the program I'm running has the filename rgbhstvla.py. I'm not sure what the error message means. Here's the python program as well:

import pyfits
import numpy as np
import pylab as py
import img_scale
from pyraf import iraf as ir

fits.open('3c68.fits', readonly)

j_img = pyfits.getdata('230UVIS.fits')
h_img = pyfits.getdata('230IR.fits')
k_img = pyfits.getdata('5GHZ.fits')

jmin,jmax = j_img.mean()+0.75*j_img.std(),j_img.mean()+5*j_img.std()
hmin,hmax = h_img.mean()+0.75*h_img.std(),h_img.mean()+5*h_img.std()
kmin,kmax = k_img.mean()+0.75*k_img.std(),k_img.mean()+5*k_img.std()

img = numpy.zeros((1024,1024,3))
img[:,:,0] = img_scale.asinh(j_img,scale_min=jmin,scale_max=jmax)
img[:,:,1] = img_scale.asinh(h_img,scale_min=hmin,scale_max=hmax)
img[:,:,2] = img_scale.asinh(k_img,scale_min=kmin,scale_max=kmax)

pylab.clf()
pylab.imshow(img)
pylab.show()

(I'm still working on the program since I'm new to python, tips here would be nice as well but they're mostly unnecessary as I'm sure I'll figure it out eventually).