Python Dataframe list of lists of dataframes into a single dataframe

Question

I have a big list consisting of 39 sublists. Each sublist has many dataframes. Now, I want to convert them into a single dataframe.

My code:

append_data = [[Dataframe,...][Dataframe,...]]
combined_csv = pd.concat(append_data) 

Present output:

    raise TypeError(msg)

TypeError: cannot concatenate object of type "<class 'list'>"; only pd.Series, pd.DataFrame, and pd.Panel (deprecated) objs are valid

Answer 1

You can do two concat

pd.concat(pd.concat(x) for  x in append_data )