How to merge 2 cells in a pandas dataframe

I have a table like:

I want to add another row at the bottom like the following where the "Total Marks" text spans over two columns ("Student id" & "Course id"):

Can anyone guide?

As far as I'm aware, pandas doesn't really support merged cells/cells spanning multiple rows in the same way as Excel/HTML do. A pandas-esque way to include the total row for a single column would be something like the following:

import pandas as pd

columns = ['Student ID', 'Course ID', 'Marks']
data = [(103, 201, 67), (103, 203, 67), (103, 204, 89)]
df = pd.DataFrame(data, columns=columns)
df.at['Total marks', 'Marks'] = df['Marks'].sum()

print(df)

(per this answer)

This gives you:

                Student ID  Course ID  Marks
0                    103.0      201.0   67.0
1                    103.0      203.0   67.0
2                    103.0      204.0   89.0
Total marks            NaN        NaN  223.0

For HTML output like the image you provided, it looks like you would have to edit the HTML after exporting from pandas (this thread talks about columns but I believe the same applies for merging cells in rows).