In Python, the list class provides a variety of methods for manipulating and accessing list data. Here’s a comprehensive list of these methods:

List Methods in Python

1. append(x)
   • Description: Adds an item x to the end of the list.
   • Usage: list.append(3)
2. extend(iterable)
   • Description: Extends the list by appending elements from the iterable.
   • Usage: list.extend([4, 5, 6])
3. insert(i, x)
   • Description: Inserts an item x at a given position i.
   • Usage: list.insert(1, 'a')
4. remove(x)
   • Description: Removes the first occurrence of an item x.
   • Usage: list.remove('b')
5. pop([i])
   • Description: Removes and returns the item at position i. If i is not specified, removes and returns the last item.
   • Usage: item = list.pop(), item = list.pop(2)
6. clear()
   • Description: Removes all items from the list.
   • Usage: list.clear()
7. index(x[, start[, end]])
   • Description: Returns the index of the first occurrence of an item x. The search can be restricted to the start and end positions.
   • Usage: list.index('b'), list.index('b', 1, 4)
8. count(x)
   • Description: Returns the number of occurrences of an item x.
   • Usage: list.count(2)
9. sort(*, key=None, reverse=False)
   • Description: Sorts the list in place. Can be customized using the key and reverse parameters.
   • Usage: list.sort(), list.sort(reverse=True), list.sort(key=lambda x: x.lower())
10. reverse()
    • Description: Reverses the elements of the list in place.
    • Usage: list.reverse()
11. copy()
    • Description: Returns a shallow copy of the list.
    • Usage: new_list = list.copy()

Example Usage

Here’s an example illustrating some of these methods:

pythonCopy code
# Initializing a list
fruits = ['apple', 'banana', 'cherry']

# Append 'orange' to the list
fruits.append('orange')
print(fruits)  # Output: ['apple', 'banana', 'cherry', 'orange']

# Extend list by adding another list
fruits.extend(['kiwi', 'mango'])
print(fruits)  # Output: ['apple', 'banana', 'cherry', 'orange', 'kiwi', 'mango']

# Insert 'lemon' at position 1
fruits.insert(1, 'lemon')
print(fruits)  # Output: ['apple', 'lemon', 'banana', 'cherry', 'orange', 'kiwi', 'mango']

# Remove 'banana' from the list
fruits.remove('banana')
print(fruits)  # Output: ['apple', 'lemon', 'cherry', 'orange', 'kiwi', 'mango']

# Pop the last item
last_item = fruits.pop()
print(last_item)  # Output: 'mango'
print(fruits)     # Output: ['apple', 'lemon', 'cherry', 'orange', 'kiwi']

# Clear the list
fruits.clear()
print(fruits)  # Output: []

# Using other methods
fruits = ['banana', 'apple', 'banana', 'cherry']
print(fruits.index('banana'))  # Output: 0
print(fruits.count('banana'))  # Output: 2
fruits.sort()
print(fruits)  # Output: ['apple', 'banana', 'banana', 'cherry']
fruits.reverse()
print(fruits)  # Output: ['cherry', 'banana', 'banana', 'apple']

These methods provide the functionality to perform common operations such as adding, removing, and sorting elements in a list.

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explain sort() in python

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