how to add two thing in list in list at same time code example

Example 1: append two items to list

my_list = ['a']
# You can use list.append(value) to append a single value:
my_list.append('b')
# my_list should look like ['a','b']

# and list.extend(iterable) to append multiple values.
my_list.extend(('b','c'))
# my_list should look like ['a','b','c']

Example 2: append two list of number to one python

listone = [1,2,3]
listtwo = [4,5,6]
mergedlist = []
mergedlist.extend(listone)
mergedlist.extend(listtwo)