Imagine you work with the following pivoted dataset df:
+----------+-----+-----+
| Letter | A | B |
| Number | | |
|----------+-----+-----|
| 1 | A1 | B1 |
| 2 | A2 | B2 |
| 3 | A3 | B3 |
+----------+-----+-----+How could you reshape the DataFrame to make it look like:
+----------+----------+-----------------+
| | Letter | Number&Letter |
| Number | | |
|----------+----------+-----------------|
| 1 | A | A1 |
| 2 | A | A2 |
| 3 | A | A3 |
| 1 | B | B1 |
| 2 | B | B2 |
| 3 | B | B3 |
+----------+----------+-----------------+Tip: Check the documentation to get the correct answer