Is there a dict.update(sub_dict) function for list in Python? (When the list is empty)

Question

Suppose a list in Python -> mylist:

mylist = []

I want to now take input from users and update the values afterward in mylist:

input1 = ["xyz","wyh",34]
print mylist
Output: [["xyz","wyh",34]]

input2 = ["yo","hey",657]
print mylist
output: [["xyz","wyh",34],["yo","hey",657]]

append() only works when list has some values already.

Yea, I'm not sure what the confusion is...perhaps we should link the documentation? — Rushabh Mehta, Aug 03 '18 at 16:02
The Python documentation involving list is [over here](https://docs.python.org/3/tutorial/datastructures.html). — user202729, Aug 03 '18 at 16:04
Also you may want to tag the question with [tag:python-2.7] or [tag:python-3.x]. — user202729, Aug 03 '18 at 16:04
Possible duplicate of [What is the syntax to insert one list into another list in python?](https://stackoverflow.com/questions/3748063/what-is-the-syntax-to-insert-one-list-into-another-list-in-python) — user202729, Aug 03 '18 at 16:07
I am sorry folks I couldn't put up my question correctly before. please check the correct version of what I want to ask! Thanks!. — Devesh Pal, Aug 03 '18 at 16:16
This is still a poor question. Many such answers are available on Stack Overflow. Please read the guidelines before asking more questions. — Rushabh Mehta, Aug 03 '18 at 16:19
For updating list options are there like append, extend, insert which are not useful for my case, unfortunately. Can you help me with a solution? :( — Devesh Pal, Aug 03 '18 at 16:28

Pyd · Answer 1 · 2018-08-03T16:09:08.747

0

you can use list.append

 mylist.append(["L","M",56])
 (or)
 mylist+[["L","M",56]]

edited Aug 03 '18 at 16:09

answered Aug 03 '18 at 16:02

Pyd

score 0 · Answer 2 · answered Aug 03 '18 at 16:03

0

I'd advise you take a look through here to see what exactly you need. It sounds like what you want is list.append() however.

mylist = [["X","Y",12], ["A","B",23]]
mylist.append(["L","M",56])

answered Aug 03 '18 at 16:03

Mark R

What if the list value is null, then it won't append. What in such cases? – Devesh Pal Aug 03 '18 at 16:19
You should initialize the list at first with mylist = [] if you don't have any initial values. Append will work on any list, even if it's empty – Mark R Aug 03 '18 at 16:34

2 Answers2