Pandas – stack multiindex header but exclude first column

I have a CSV file which I read into a panda dataframe using a multiindex header. Here is an example:

df = pd.DataFrame([[1,5,5,2,3], [2,10,4,20,3]])
df.columns = pd.MultiIndex.from_tuples((("1/1/2024","Store"), ("product code 1", "quantity onhand"), ("product code 1",'quantity sold'), ("product code 2", "quantity onhand"), ("product code 2",'quantity sold')))
df

The date in the first column is not needed. I tried to stack, but I need to retain the store as it is. Can this be done using pivot to get the following result?

data = [[1,'product code 1',5,5],[1,'product code 2',3,2],[2,'product code 1',4,10],[2,'product code 2',3,20]]
columns = ['Store','Code','quantity sold','quantity onhand']
df2 = pd.DataFrame(data, columns=columns)
df2

>Solution :

You can temporarily set the first column as index, then stack:

(df.set_index(df.columns[0])
   .stack(0)
   .rename_axis(['Store', 'Code'])
   .reset_index()
)

Output:

   Store            Code  quantity onhand  quantity sold
0      1  product code 1                5              5
1      1  product code 2                2              3
2      2  product code 1               10              4
3      2  product code 2               20              3