Python Dataframe fillna 左列有值

Question

I have an excel spreadsheet where there are merged cells.

I would like to build a dictionary of Product_ID - Category - Country.

But for that I need to get, I believe, Python to be able to read an excel file with horizontally merged cells.

import pandas as pd

excel_sheet = pd.read_excel(r'C:\Users\myusername\Documents\Product_Sales_Database.xlsx, 'Product IDs')

However the returned dataframe is this:

My question is, how can I fill the nan values in the dataframe, with the values on the left column?

Thank you!

Answer 1

This should do:

df.iloc[0] = df.iloc[0].ffill() 

Answer 2

I understand, that the question is more than 2 yo, and the best answer is correct, but if you want to fill NaNs of the whole Frame, you can use:

df.T.ffill().T