Lists Methods
The List data type has some important methods to make it useful.
append( ) : Add or append an item to the end of the list.
Syntax: list.append( item )
list = [1, 2, 3, 4, 5, 6]
list.append( 7 )
print( list )
Output:
extend( ) : Extend the list by appending all the items of the other
list
Syntax: list_1.extend( list_2 )
list_1 = [1, 2, 3, 4, 5, 6]
list_2 = [7, 8, 9, 10, 11]
list_1.extend( list_2 )
print( list_1 )
Output:
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
insert( ) : Insert an item at the given position. If position is not
provided then the
item will be added to end of the list.
Syntax: list_1.insert( pos, item )
list_1 = [1, 4, 9, 25, 36]
list_1.insert( 3, 16 )
print( list_1 )
list_1.insert( 49)
print( list_1 )
Output:
[1, 4, 9, 16, 25, 36]
[1, 4, 9, 16, 25, 36, 49]
remove( ) : Remove the first occurrence of the given item in the
list. If no such item in
the list exists then, it raises ValueError.
Syntax: list_1.remove( item )
list_1 = [1, 4, 9, 25, 36]
list_1.remove( 25 )
print( list_1 )
pop( ) : Pop off the item at the given index in the list and return
it. If index is not
provided then, it pops off the last item and returns it.
Syntax: list_1.pop( [index] )
list_1 = [1, 4, 9, 25, 36]
list_1.pop( [2] )
count( ) : Return the number of times the given item appears in the
list.
Syntax: list_1.count( item )
list_1 = [1, 4, 9, 25, 36, 25]
list_1.count( 25 )
clear( ) : Empty the whole list.
Syntax: list_1.clear( )
list_1 = [1, 4, 9, 25, 36, 25]
list_1.clear( )
print( list_1 )
sort ( ) : Sort the list items in the preferred order.
Syntax: list_1.sort( key = None, reverse = False )
list_1 = [5, 1, 4, 6, 0, 8]
list_1.sort( )
print( list_1
)
// sorts in ascending order
list_1.sort( reverse = True )
print( list_1
)
// sorts in
descending order
Output:
[0, 1, 4, 5, 6, 8]
[8, 6, 5, 4, 1, 0]
reverse( ) : Reverse the items of the list in place.
Syntax: list_1.reverse( )
list_1 = [1, 4, 9, 25, 36]
list_1.reverse( )
print( list_1 )
Output: