Column List of Dictionaries Create Columns

I have a column, X, where the rows' values are a list of dictionaries. I.e.

row 1 = [{category: **1**, outcome: 1444}, {category: **3**, outcome: 12}, {category: **3**, outcome: 11},... ]

row 2 = [{category: 2, outcome: 1555}, {category: 5, outcome: 42},...]

How can I create columns of each key present in X to then populate with values from the list of dictionaries from each row?

So for row 1, I'd populate a column, 1, with 1444... and column 3, with 12, 11 (2 values separated by a comma).

Here's one way to solve it.

Given:

row 1 = [{category: 1, outcome: 1444}, {category: 3, outcome: 12}, {category: 3, outcome: 11},... ]

row 2 = [{category: 2, outcome: 1555}, {category: 5, outcome: 42},...]

Format the rows so that they look like:

new_row_1 = { 
     1: [1444, ...],
     3: [1444, 12, ...], 
      ...
}

new_row_2 = {
     2: [1555, ...], 
     5: [42, ...],
     ...
}

Then, you can just loop over each row and call .join().

Here is some pseudocode :)

RESULT_GROUPS = {}
FOREACH row_id, row in rows
   FOREACH item in row
      RESULT_GROUPS[row_id][ item[category] ] = item[value]

   FOREACH group_id, group in RESULT_GROUPS[row_id]
      RESULT_GROUPS[row_id][ group_id ] = group.join(',')