text: import matplotlib.pyplot as plt
  import astropy
  import numpy as np
  from astropy.convolution import convolve as ap_convole
  from astropy.convolution import Box2DKernel
  
  nx=30;ny=30;
  a=np.random.normal(size=(nx,ny))
  plt.plot(a.flatten())
  plt.show()
  
  b2dk=Box2DKernel(9)
  ac=ap_convole(a,b2dk)
  plt.plot(ac.flatten())
  plt.show()
  