docs(merge_two): use stdin to generate the second dictionary

subjects/devops/merge_two/README.md

@@ -4,12 +4,15 @@ One very useful data structure in Python are the dictionaries, in this exercise
 
 ### Instructions
 
-Create a file `merge_two.py` which will have a function named `merge_two()`. This function will accept two dictionaries, create a third one which will be the merge of the two inputs and return it as a serialized JSON string.
+Create a file `merge_two.py` which will have a function named `merge_two()`. This function will accept one dictionary.
+It will prompt the user to create a new dictionary asking for keys and values.
+
+As a return it will create a third one which will be the merge of the two dictionaries and return it as a serialized JSON string.
 
 Here is the prototype of the function:
 
 ```python
-def merge_two(first_dict, second_dict):
+def merge_two(first_dict):
     # this is a function,
     # write your code here
 ```
@@ -26,31 +29,43 @@ first = {
     "Louise": 23,
     "Lea": 34
 }
-second = {
+
-    "Louise": 44,
+print(merge_two(first))
-    "Romolo": 30,
-    "Lea": 22
-}
-print(merge_two(first, second))
 ```
 
 Run your test file with the following command:
 
 ```console
 $ python3 test.py
+Add a new entry:
+key: Louise
+value: 44
+Add a new entry:
+key: Romolo
+value: 30
+Add a new entry:
+key: Lea
+value: 22
+Add a new entry:
+key: exit
 {"Bob": 36, "Louise": 44, "Lea": 22, "Romolo": 30}
 $
 ```
 
 ### Hints
 
-- If a key is repeated in both dictionaries the value retained will be the one in `second_dict`.
+- If a key is repeated in both dictionaries the value retained will be the last one.
 
 - There are different ways to merge dictionaries, take the time to understand the differences in between those techniques and try more than one technique to better retain it.
 
 - Add `import json` to use the standard functions for JSON manipulation.
 
+- Use the function `input()` to read from `stdin` and `int()` to convert the value to a number.
+
+> Your solution will be tested only for valid inputs (all the values will be convertible to `int`).
+
 ### References
 
 - [Merging dictionaries in Python](https://www.geeksforgeeks.org/python-merging-two-dictionaries/)
 - [JSON library in Python](https://docs.python.org/3/library/json.html)
+- [Function input() in Python](https://www.w3schools.com/python/ref_func_input.asp)