How to complete the list?

Question

Python

Let's say I have a list: How can I put new data to come out: And how can I make it so that if in 2: abc, def, 123. Then in 1 add: xyz, "", ""
data = {"1": ["xyz", ""]}

{"1": ["xyz", ""], "2": ["abc", "def"]}

Answer 1

so list or dictionary?
your example is like this:
data["2"] = ["abc", "def"]

Answer 2

The second question was solved with this solution:

long = 0
    for val in data.values():
        if long < len(val):
            long = len(val)

    for val in data.values():
        add_long = long - len(val)
        for row in range(add_long):
            val.append('')