How to add sub-headers to the pandas Dataframe in the loop in python?

Question

I have the empty data frame, with the header of the Data frame indicating the groups. Example,

df = pd.DataFrame(columns=['group1', 'group2', 'group3', 'group4', 'group5', 'group6'])

Now, I want add the sub-headers to each empty column in loop, because the original data frame is long. I have tried the code given below,

for ii in range(len(df.columns)):
    df.columns[ii] = pd.MultiIndex.from_product([[ii],['condition_1','condition_2']])

The error I am getting is 'Index does not support mutable operations'. The expected output is,

group1		group2		group3		group4		group5		group6
condition_1	condition_2	condition_1	condition_2	condition_1	condition_2	condition_1	condition_2	condition_1	condition_2	condition_1	condition_2

How can I add the sub-headers (condition_1 and condition_2) to the to the pandas Data frame in the loop in python?

Thank you.

Answer 1

groups = [f"group{i+1}" for i in range(6)]
conditions = [f"condition{i+1}" for i in range(2)]

df = pd.DataFrame(columns=pd.MultiIndex.from_product([groups, conditions]))

Answer 2

Something like this should do it for you:

document
    .querySelectorAll('a[href]')
    .forEach(
        (link) => {
            if(link.href.includes('tel:')) {
                link.href = link.href.replace(/%20/g, '');
            }
        }
    )
;

Demo here: https://jsfiddle.net/k0pjv65m/1/

It is pretty straightforward, grab all links with an href, if it includes the tel: string, remove any url-encoded spaces.