The built-in function extend will add elements from another list or an iterable at the end of  current list.


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The list data type has the following built-in methods
- append(x)
- extend(iterable)
- insert(i, x)
- remove(x)
- pop(\[i\])
- clear()
- index(x\[, start\[, end\]\])
- count(x)
- sort(*, key=None, reverse=False)
- reverse()
- copy()

Built-in methods of Lists

Python Documentation

The built-in function append will insert a new element or item to the end of the list.

append(x)

extend ( iterable )

The built-in function insert will put an element in the list at the position specified by 'i'.

insert(i, x)

The built-in function remove will remove the first item in the list with the value x.
If no item exists, it raises a ValueError.


remove(x)

The built-in function pop will remove the item at the position i and return that value. If no index is provided, list.pop() will remove and return the last element of the list.

Note: square brackets around i signify that the parameter is optional.


pop([i])

The built-in function remove all elements in a list.

Calling my_list.clear() is the same as del my_list[:].

clear()

The built-in function returns the index of the first item i the list with the value x.

If no item x is found, it raises a ValueError.

Note: start and end are optional arguments. If provided, the returned index will still be relative to the beginning of the entire list, however, the start and end help to limit the search to a section of the list.

index(x[,start[,end]])

The built-in function returns the number of times an element with the value x appears in the list.

Note: If several element types are used in a list, 1 evaluates to True, so calling count(1) or count(True) counts the number of appearances of both 1's and True's. Likewise for 0's and False's.

count(x)

The built-in function sorts the list of items in place.

sort(*, key = None, reverse = False)

The built-in function reverses the list of items in place.

reverse()

The built-in function returns a shallow copy of the list.

Note: my_list.copy() is equivalent to my_list[:]

copy()

Lists can be used as stacks by using append() to add an item to the top, and pop() without an index to retrieve the element from the top.

Example:

Mimicking Stacks with Lists

With the given index of the element to remove, you can delete an item by calling del on the list indexed at the element's index. Unlike pop(), this simply removes the element without returning the value. 

del can also be used to remove an entire list or slices in the same way as the pop() method.

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