Как я могу сгруппировать по приведенной ниже таблице из идентификатора клиента и кода продукта и поместить их в одну строку?

df[''] = df.groupby(['Customer ID', 'Product Code']).cumcount()
df = df.pivot(index=['Customer ID', 'Product Code'], columns='')
print(df)

Выход:

                         Days since the last transaction
                                                       0     1    2
Customer ID Product Code
A           1                                       10.0  23.0  7.0
            2                                        8.0   9.0  NaN
            3                                        6.0   NaN  NaN
B           1                                       18.0   NaN  NaN
            2                                        4.0   NaN  NaN
            3                                        4.0  12.0  NaN
C           2                                       27.0  15.0  NaN

Ниже код Python также работал у меня.

#keep only the needed data
grouped = df.groupby(['Customer_ID','Product Code'], as_index=False).agg({"Days since the last transaction": lambda x: x.tolist()[:3]+[x.iat[-1]]}).explode("Days since the last transaction")

#get the count for the age columns
grouped["idx"] = grouped.groupby(['Customer_ID','Product Code']).cumcount().add(1)

#pivot to get the required structure
output = grouped.pivot(["Customer_ID","Product Code"],"idx","Days since the last transaction").add_prefix("Days since the last transaction").reset_index().rename_axis(None, axis=1)

output.head()