Concatenating a series of strings into a single string within a Pandas Dataframe column (for each row)?

Question

This is really throwing me for a loop. In a pandas dataframe (df) I have the following:

date	News
2021-02-03	Some random event occurred today.
2021-02-03	We asked a question on Stack Overflow.
2021-02-02	The weather is nice.
2021-02-02	Hello. World.

The date column is the index which is of the date format, and the News column is a string. What I want to do is to combine the duplicate dates and join or concatenate the News column, for example:

date	News
2021-02-03	Some random event occurred today. We asked a question on Stack Overflow.
2021-02-02	The weather is nice. Hello. World.

So far, I have:

df = df.groupby(['date']).agg({'News': list})

However, while this does combine the duplicated dates, it puts the string values in a list, or rather according to the errors I've been getting while trying to join them, into a series. At this point, I am completely lost and any hint/tip to lead me to the right pythonic way of doing this would be greatly appreciated!

PS: I would like to avoid using a loop if at all possible since this will need to parse through roughly 200k records multiple times (as a function). If it makes any difference, I'll be using TextBlob on the News column to perform sentiment analysis on.

Answer 1

Quang Hoang answered the question perfectly! Although I'm not able to mark it as the answer sadly =(

df.groupby('date')['News'].agg(' '.join). – Quang Hoang Feb 8 at 15:08