pandas to pickle
# use pickle format to save columns with complex data (like list)
# and keep their structure
>>> original_df = pd.DataFrame({"foo": range(5), "bar": range(5, 10)})
>>> original_df
foo bar
0 0 5
1 1 6
2 2 7
3 3 8
4 4 9
>>> original_df.to_pickle("./dummy.pkl") # use read_pickle to read the dataframe