List Methods

Python lists have several built-in methods that allow you to perform various operations on lists. Here are some commonly used list methods:

1. append(x): Adds an element x to the end of the list.

   numbers = [1, 2, 3]
   numbers.append(4)
   # Now, numbers is [1, 2, 3, 4]

2. extend(iterable): Extends the list by appending elements from the iterable.

   numbers = [1, 2, 3]
   numbers.extend([4, 5, 6])
   # Now, numbers is [1, 2, 3, 4, 5, 6]

3. insert(i, x): Inserts element x at the specified index i.

   numbers = [1, 2, 3]
   numbers.insert(1, 10)
   # Now, numbers is [1, 10, 2, 3]

4. remove(x): Removes the first occurrence of element x from the list.

   numbers = [1, 2, 3, 4, 3, 5]
   numbers.remove(3)
   # Now, numbers is [1, 2, 4, 3, 5]

5. pop([i]): Removes and returns the element at index i. If i is not provided, it removes and returns the last element.

   numbers = [1, 2, 3, 4, 5]
   popped_value = numbers.pop(2)
   # Now, numbers is [1, 2, 4, 5], and popped_value is 3

6. clear(): Removes all elements from the list, leaving it empty.

   numbers = [1, 2, 3, 4, 5]
   numbers.clear()
   # Now, numbers is []

7. index(x[, start[, end]]): Returns the index of the first occurrence of element x in the list. Optionally, the search can be limited to the specified range [start:end].

   numbers = [1, 2, 3, 4, 5]
   index_of_3 = numbers.index(3)
   # index_of_3 is 2

8. count(x): Returns the number of occurrences of element x in the list.

   numbers = [1, 2, 3, 4, 3, 5]
   count_of_3 = numbers.count(3)
   # count_of_3 is 2

9. sort(key=None, reverse=False): Sorts the elements of the list in ascending order. The key and reverse parameters allow customization.

   numbers = [4, 2, 1, 3, 5]
   numbers.sort()
   # Now, numbers is [1, 2, 3, 4, 5]

10. reverse(): Reverses the elements of the list in-place.

    numbers = [1, 2, 3, 4, 5]
    numbers.reverse()
    # Now, numbers is [5, 4, 3, 2, 1]

These are just a few examples of the many list methods available in Python. Understanding and using these methods can greatly simplify list manipulation tasks in your programs.