Understanding *args and **kwargs in Python Functions

I have used *args and **kwargs for years by copy-pasting patterns I found on Stack Overflow.   Today I actually understand them.   The simple version: *args = accept any number of positional arguments as a tuple **kwargs = accept any number of keyword arguments as a dictionary   Why does this matter in data work?   Imagine a validation function. You want it to accept any number of rules — not just 2, not just 5. Any number.   Without *args: def validate(data, rule1, rule2, rule3): # what if I have 10 rules?    pass   With *args: def validate(data, *rules):    for rule in rules:        if not rule(data):            print(f'Failed: {rule.__name__}')   Now I can call: validate(df, check_nulls, check_schema, check_dates, check_amounts)   Any number of rules. Clean interface. One function definition.   **kwargs is for when the rules need configuration: validate(data, null_threshold=0.05, date_column='txn_date')   The insight from Corey: *args and **kwargs are not advanced Python. They are the way Python lets functions be flexible. Once you see that, they become obvious.   What patterns clicked for you only after someone explained WHY, not just HOW?   ---- #Python #LearningInPublic #DataEngineering #CodingTips #PythonFunctions

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