I am trying to automatically merge columns of tables using docxtpl on python.

My tables are in the following form:

context = {
'tbl_contents': [
    {'label': '1', 'cols': ['A','A','B']},
    {'label': '2', 'cols': ['C', 'C', 'B'},
    {'label': '3', 'cols': ['A', 'E', 'D']},
    ]
}

The table is then dynamically filled, iterating on lines

I would like to be able to horizontally merge all cells containing the same character, to turn this:

  +---+---+---+
1 | A | A | B |
  +---+---+---+
2 | C | C | B |
  +---+---+---+
3 | A | E | D |
  +---+---+---+

into this:

  +---+---+---+
1 | A   A | B |
  +-------+---+
2 | C   C | B |
  +---+---+---+
3 | A | E | D |
  +---+---+---+

I saw that on Github there is a script that vertically merges cells of a docx-tpl document, but it does not seem to do it horizontally.

I also saw in this post that with python-docx there seems to be a way to merge cells.

Does anybody have an answer to this problem?