Replace hard-coded file output with \!head

Author: rossbar

content/save-load-arrays.md

@@ -187,18 +187,8 @@ np.savetxt("x_y-squared.csv", X=array_out, header="x, y", delimiter=",")
 
 Open the file, `x_y-squared.csv`, and you'll see the following:
 
-```
-# x, y
-0.000000000000000000e+00,0.000000000000000000e+00
-1.000000000000000000e+00,1.000000000000000000e+00
-2.000000000000000000e+00,4.000000000000000000e+00
-3.000000000000000000e+00,9.000000000000000000e+00
-4.000000000000000000e+00,1.600000000000000000e+01
-5.000000000000000000e+00,2.500000000000000000e+01
-6.000000000000000000e+00,3.600000000000000000e+01
-7.000000000000000000e+00,4.900000000000000000e+01
-8.000000000000000000e+00,6.400000000000000000e+01
-9.000000000000000000e+00,8.100000000000000000e+01
+```{code-cell}
+!head x_y-squared.csv
 ```
 
 ## Our arrays as a csv file