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List Methods in Python

 


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List Methods in Python

Python lists come with a variety of built-in methods that allow you to perform common operations. Here are some of the most frequently used list methods:

1. append()

Adds an item to the end of the list.

# Example of append()
my_list = [1, 2, 3]
my_list.append(4)
print(my_list)  # Output: [1, 2, 3, 4]

2. extend()

Extends the list by appending all the items from another list.

# Example of extend()
list1 = [1, 2, 3]
list2 = [4, 5]
list1.extend(list2)
print(list1)  # Output: [1, 2, 3, 4, 5]

3. insert()

Inserts an item at a specified position.

# Example of insert()
my_list = [1, 2, 4]
my_list.insert(2, 3)
print(my_list)  # Output: [1, 2, 3, 4]

4. remove()

Removes the first occurrence of a specified value.

# Example of remove()
my_list = [1, 2, 3, 4]
my_list.remove(3)
print(my_list)  # Output: [1, 2, 4]

5. pop()

Removes and returns an item at a specified index. If no index is specified, it removes and returns the last item.

# Example of pop()
my_list = [1, 2, 3, 4]
item = my_list.pop(2)
print(item)  # Output: 3
print(my_list)  # Output: [1, 2, 4]

6. clear()

Removes all items from the list.

# Example of clear()
my_list = [1, 2, 3, 4]
my_list.clear()
print(my_list)  # Output: []

7. index()

Returns the index of the first occurrence of a specified value.

# Example of index()
my_list = [1, 2, 3, 4]
index = my_list.index(3)
print(index)  # Output: 2

8. count()

Returns the number of occurrences of a specified value.

# Example of count()
my_list = [1, 2, 3, 2, 2]
count = my_list.count(2)
print(count)  # Output: 3

9. sort()

Sorts the list in ascending order by default. Can take a parameter reverse=True to sort in descending order.

# Example of sort()
my_list = [4, 2, 3, 1]
my_list.sort()
print(my_list)  # Output: [1, 2, 3, 4]

10. reverse()

Reverses the order of the list.

# Example of reverse()
my_list = [1, 2, 3, 4]
my_list.reverse()
print(my_list)  # Output: [4, 3, 2, 1]
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