You are given the first 5 rows of a pandas dataframe called df which contains the data below: 
        Date  Country  Sales
0 2023-01-01  Lebanon     10
1 2023-02-01  Lebanon     20
2 2023-03-01  Lebanon     30
3 2023-04-01  Lebanon    150
4 2023-05-01  Lebanon     50
Answer the following question using Python code: Which country had the highest sales in 2023?

Do not define a new dataframe df, do not show it in the code

The Date column should be used to filter specific months or years 

Only output the Python code without explanation, be sure to use the right formatting

Put the final answer in a variable called res_df  Please reply with exactly 3 paragraphs and separate each paragraph with two new lines. The very first paragraph must start with the word "monitoring".
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