readme: add join training set instruction

README.md

@@ -1,3 +1,21 @@
 ---
 license: wtfpl
 ---
+
+# To join all training set files together
+Use this script https://stackoverflow.com/a/57422761, copied here for redundancy:
+
+```python
+files=['my.json','files.json',...,'name.json']
+
+def merge_JsonFiles(filename):
+    result = list()
+    for f1 in filename:
+        with open(f1, 'r') as infile:
+            result.extend(json.load(infile))
+
+    with open('counseling3.json', 'w') as output_file:
+        json.dump(result, output_file)
+
+merge_JsonFiles(files)
+```