Python OOP for Django Development

Day 20 of my Python Full Stack journey. ✅ Today I did something most learners skip. Revision. Before jumping into — Advanced Python + Django — I went back and revised everything from first 4 weeks. Here's what I revised today: → Variables, Data Types, f-strings → Conditionals — if, elif, else → Loops — for, while, range() → Functions — *args, **kwargs, default arguments → Lists, Dictionaries, Tuples, Sets → Nested Data Structures → File Handling — read, write, append → OOP — Classes, Methods, Inheritance Why revision matters: Moving fast feels productive. But building on a shaky foundation always breaks later. Today I made sure my foundation is solid. So when Django hits — nothing feels alien. One thing that surprised me during revision: How much more sense OOP makes now compared to Day 16. Same concept. Completely different level of understanding. That's what consistency does. 💪 Day 21 tomorrow — Month 2 officially begins. List comprehensions, Lambda, Map, Filter. Advanced Python starts now. 🚀 What's the one Python concept you wish you had revised before moving to Django? #PythonFullStack #Day21 #Revision #BuildingInPublic #100DaysOfCode #Bangalore

Day 14 of my Python Full Stack journey. ✅ Today's topic: File Handling — making data survive after the program closes. This is where Python stops feeling like exercises and starts feeling like real software. Here's what I typed today: # Writing to a file with open("students.txt", "w") as file: file.write("Punith: 88\n") file.write("Rahul: 92\n") # Reading from a file with open("students.txt", "r") as file: content = file.read() print(content) # Appending to a file with open("students.txt", "a") as file: file.write("Priya: 76\n") Biggest lesson today: Always use 'with open()' instead of just open(). It automatically closes the file even if an error occurs. One line saves you from a lot of headaches. ✅ Why this matters for Django: → Django reads config files on startup → Log files track every request your app receives → Media uploads are files stored on your server Understanding file I/O now makes all of that make sense later. Two weeks done. Still showing up every single day. 💪 #PythonFullStack #Day14 #BuildingInPublic #100DaysOfCode #Bangalore

Day 18 of my Python Full Stack journey. ✅ Today's topic: Inheritance — one of the most powerful concepts in OOP. Instead of writing the same code twice — you inherit it from a parent class. Here's what I typed today: # Parent class class Person: def __init__(self, name, age): self.name = name self.age = age def introduce(self): return f"Hi, I'm {self.name}, {self.age} years old." # Child class — inherits from Person class Student(Person): def __init__(self, name, age, course): super().__init__(name, age) # inherits parent __init__ self.course = course # Method overriding — redefining parent method def introduce(self): return f"Hi, I'm {self.name}. I study {self.course}." s1 = Student("Punith", 24, "Python Full Stack") print(s1.introduce()) # Hi, I'm Punith. I study Python Full Stack. 3 things that clicked today: → super() calls the parent class — no need to rewrite __init__ → Child class can override any parent method → Child class can also add brand new methods of its own Why this matters for Django: → Django's Model class is a parent class → When you write 'class Student(models.Model)' — you are inheriting from Django's Model → That one line gives your class database superpowers #PythonFullStack #Day18 #Inheritance #OOP #BuildingInPublic #100DaysOfCode #Bangalore

5 books. 6 database trips. That's your Django app bleeding performance. Most of the time we never notice the N+1 problem — until their app slows down under real data. Here's the fix explained as a story (swipe through) 👇 𝗦𝗹𝗶𝗱𝗲 𝟭 — You have 5 books. Each has an author. Simple. 𝗦𝗹𝗶𝗱𝗲 𝟮 — Without optimization: Django makes 6 separate DB trips. One per book. Painful. 𝗦𝗹𝗶𝗱𝗲 𝟯 — select_related() fixes it with a single JOIN. 1 trip. Everything together. 𝗦𝗹𝗶𝗱𝗲 𝟰 — But JOIN breaks with tags — Book 1 repeats 3 times. Messy. 𝗦𝗹𝗶𝗱𝗲 𝟱 — prefetch_related() makes 2 smart trips. Python glues them in memory. 𝗦𝗹𝗶𝗱𝗲 𝟲 — The rule: ONE thing → select_related. MANY things → prefetch_related. That's it. Two methods. One simple rule. #Django #Python #WebDevelopment #BackendDevelopment #SoftwareEngineering

𝗧𝗵𝗶𝘀 𝗜𝘀 𝗗𝗮𝘆 𝟲𝟯 𝗼𝗳 #𝟭𝟬𝟬𝗗𝗮𝘆𝘀𝗢𝗳𝗖𝗼𝗱𝗲 I continued my Python refresher and introduced Django. Yesterday, I covered Python basics. Today, I dove into functions and object-oriented programming \(OOP\) because these are essential for understanding Django. You define a function in Python using the def keyword. For example: - def greet\(name\): return f"Hello, \{name\}!" - print\(greet\("Haris"\)\) # Hello, Haris! Functions have powerful features: - You can assign default values to parameters - Use \*args to collect extra positional arguments into a tuple - Use \*\*kwargs to collect extra keyword arguments into a dictionary You can use these together. The order matters: regular args, \*args, \*\*kwargs. Python is fully object-oriented. You define classes and use \_\_init\_\_ as the constructor. - class Person: - def \_\_init\_\_\(self, name, age\): self.name = name, self.age = age - def introduce\(self\): return f"Hi, I'm \{self.name\} and I'm \{self.age\} years old." I also looked at how Django structures projects. A project is the entire web application, and you organize functionality into smaller units called apps. - Each app handles one specific part of your project - You create an app using python manage.py startapp posts This keeps your code modular and clean. Source: https://lnkd.in/g4YgFWMu

Understanding Django's .get_or_create() Pattern A pattern I see frequently misunderstood in Django codebases: This returns a tuple of (instance, boolean). The comma performs standard Python iterable unpacking—it's not Django-specific syntax. Common mistake: Treating the unpacked variables as a single unit. They're independent references. obj is a fully editable model instance, and created is simply a boolean indicating whether a new record was inserted. Practical application—handling placeholder records: Consider a ProjectMembership model where new clients are created with project=None as a placeholder. This pattern: Finds the existing placeholder if present Creates one if absent Updates the project reference in either case Result: The placeholder is upgraded rather than orphaned. No duplicate records. No cleanup required. Key takeaway: .get_or_create() followed by assignment provides atomic-like "get or upsert" semantics without race conditions that plague separate get-then-create logic. This protection only works if there's a database-level unique constraint on the lookup fields (or Django's unique_together in Meta). Without it, .get_or_create() still has a race condition window. The database constraint is what guarantees atomicity. #Django #Python #BackendEngineering #SoftwareDevelopment

🚀From Basic Coding to Building with Python, Django & Al The Journey Matters We all start somewhere. Writing simple print statements, fixing small errors, and understanding logic step by step. It may feel slow at first, but that foundation is everything. Getting Comfortable with Python As you learn more, Python becomes less intimidating. Functions, modules, and syntax start to make sense. You move from confusion to clarity. Unlocking the Power of Libraries Then comes the real boost. Libraries like NumPy, Pandas, and Requests help you do more with less effort. You stop reinventing the wheel and start building faster. Leveling Up with Django & Al Now you're not just coding, you're creating real-world applications. Web apps, APIs, and even Al-powered solutions. This is where things get exciting. The Takeaway Growth in tech is gradual but powerful. Stay consistent, keep building, and trust the process. The transformation is real. #Python #Django #ArtificialIntelligence #Programming #CodingJourney #DeveloperLife #SoftwareDevelopment #LearnToCode #TechGrowth #AlProjects

Not all Python backend frameworks are the same 🤯 If you're new to backend or just curious how apps are built, here’s a simple breakdown: 🔹 Flask → Lightweight & flexible 👉 You build everything yourself 🔹 Django → Full-stack framework 👉 Comes with admin panel, auth, database tools 🔹 FastAPI → Fast & modern 👉 Built for high-performance APIs 💡 Simple way to understand: Flask = Empty kitchen 🍳 Django = Full restaurant 🍽️ FastAPI = Smart automated kitchen ⚡ Each one is powerful — it just depends on your use case 👉 Which one do you prefer or want to learn? #Python #BackendDevelopment #Django #FastAPI #Flask #WebDevelopment #Programming #TechExplained

📌 One thing I underestimated while learning Django: The database. At first, I thought: "Models are just tables." But while building projects, I realized: 👉 Database design decides how clean your backend will be. Bad design = complicated queries + repeated logic + messy relationships Good design = simpler views + cleaner APIs + better performance Now I spend more time thinking about models before writing views. Your code depends on your data structure more than you think. Do you plan your database first or just start coding? #Django #BackendDevelopment #Python #LearningInPublic