Moved the third code snippet from "working with python arrays" into the...

Moved the third code snippet from "working with python arrays" into the examples directory for testing.

docs/examples/tutorial/array/unsafe_usage.pyx

+from cpython cimport array
+import array
+
+cdef array.array a = array.array('i', [1, 2, 3])
+
+# access underlying pointer:
+print(a.data.as_ints[0])
+
+from libc.string cimport memset
+
+memset(a.data.as_voidptr, 0, len(a) * sizeof(int))

docs/src/tutorial/array.rst

@@ -54,18 +54,7 @@ functions, it is possible to access the underlying contiguous array as a
 pointer. There is no type or bounds checking, so be careful to use the
 right type and signedness.
 
-::
-
-    from cpython cimport array
-    import array
-
-    cdef array.array a = array.array('i', [1, 2, 3])
-
-    # access underlying pointer:
-    print(a.data.as_ints[0])
-
-    from libc.string cimport memset
-    memset(a.data.as_voidptr, 0, len(a) * sizeof(int))
+.. literalinclude:: ../../examples/tutorial/array/unsafe_usage.pyx
 
 Note that any length-changing operation on the array object may invalidate the
 pointer.