List Deduplication Techniques

Naive Iteration Method

original_data = [7, 2, 8, 2, 7, 5]
unique_results = []
for element in original_data:
    if element not in unique_results:
        unique_results.append(element)

Set Conversion Approach

distinct_set = set([4, 4, 9, 2, 9])
unique_list = list(distinct_set)

List Comprehension with Enumerate

def deduplicate(items):
    return [val for idx, val in enumerate(items) 
            if val not in items[:idx]]

Ordered Dictionary Method

from collections import OrderedDict
duplicated = [3, 3, 1, 4, 1]
result = list(OrderedDict.fromkeys(duplicated))

Python Object Type Identification

print(type(42))                   # Output: <class 'int'>
print(isinstance([], list))       # Output: True
print("text".__class__)           # Output: <class 'str'>

Regular Expression Greedy vs Lazy Matching

import re
html_content = "<div><span>Content</span></div>"

# Greedy match
print(re.findall(r'<.*>', html_content))  
# Output: ['<div><span>Content</span></div>']

# Lazy match
print(re.findall(r'<.*?>', html_content)) 
# Output: ['<div>', '<span>', '</span>', '</div>']

PEP8 Coding Standards

• Four-space indentation
• 79-character line limits
• snake_case for variables/functions
• CamelCase for class names
• Space around operators

Django Architecture Patterns

MTV Components

• Model: Data layer with ORM
• Template: Presentation layer (HTML)
• View: Business logic handler

QuerySet Operations

from django.db.models import F, Q

# F: Reference field values in queries
Product.objects.update(price=F('price') * 1.1)

# Q: Complex query conditions
User.objects.filter(Q(age__gt=30) | Q(is_staff=True))

RESTful API Principles

• Resource-based URI design
• HTTP methods: GET/POST/PUT/DELETE
• Stateless interactions
• HATEOAS linking

Django REST Framework Features

• Serializer transformations
• Viewsets for CRUD operations
• Token authentication
• Browsable API interface

Database Technologies

Redis Use Cases

• Caching layer acceleration
• Session storage
• Distributed locking
• Rate limiting
• Leaderboard implementation

MySQL Architecture

• Connection layer: Session handling
• Service layer: Query parsing/optimization
• Engine layer: InnoDB/MyISAM handlers
• Storage layer: Filesystem persistence

InnoDB vs MyISAM

• InnoDB: ACID transactions, row-level locking
• MyISAM: Table-level locking, faster reads

Concurrency Patterns

Python Async IO

import asyncio

async def fetch_data():
    await asyncio.sleep(1)
    return "Processed"

async def main():
    result = await fetch_data()
    print(result)

asyncio.run(main())

Java Thread Pools

ExecutorService pool = Executors.newFixedThreadPool(4);
pool.submit(() -> System.out.println("Task executed"));
pool.shutdown();

Web Security Practices

Duplicate Form Submision Prevention

• Backend: Token validation mechanisms
• Frontend: Button disabling during processing
• Database: Unique constraint enforcement

Redis Cache Strategies

• Cache penetration: Null caching and Bloom filters
• Cache avalanche: Expiration time randomization
• Cache breakdown: Hotkey replicasion and mutex locks

Network Protocols

HTTP Version Evolution

• HTTP/1.1: Persistent connections
• HTTP/2: Binary framing and multiplexing
• HTTP/3: QUIC protocol with UDP transport

RPC vs HTTP

• RPC: Service contract definitions, direct method invocation
• HTTP: Resource-oriented interactions, uniform interface

Django Middleware Components

• SecurityMiddleware: HTTP header protection
• SessionMiddleware: User session management
• CsrfViewMiddleware: Cross-site request forgery prevention
• AuthenticationMiddleware: User credential handling

Python Language Concepts

Memory Management

• Reference counting
• Generational garbage collection
• Cycle detection

Execution Contexts

def outer():
    closure_var = 10
    def inner():
        return closure_var + 5
    return inner

func = outer()
print(func())  # Output: 15