How can I implement data structures in Python?

How can I implement data structures in Python?

You can implement data structures in Python using built-in types like lists, dictionaries, and sets, or by creating custom classes.

Can you show me an example of a stack implementation?

Sure! Here's a simple stack implementation using a class:

class Stack:
    def __init__(self):
        self.items = []

    def push(self, item):
        self.items.append(item)

    def pop(self):
        return self.items.pop() if not self.is_empty() else None

    def is_empty(self):
        return len(self.items) == 0

    def peek(self):
        return self.items[-1] if not self.is_empty() else None

    def size(self):
        return len(self.items)

What about implementing a queue?

Here's a simple queue implementation:

class Queue:
    def __init__(self):
        self.items = []

    def enqueue(self, item):
        self.items.insert(0, item)

    def dequeue(self):
        return self.items.pop() if not self.is_empty() else None

    def is_empty(self):
        return len(self.items) == 0

    def size(self):
        return len(self.items)