0422-python import

Sure — here’s a concise and clear summary of how Python handles from xxx import abc:

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🧵 Summary: What Happens When You from xxx import abc

Step	What Python Does	Why
✅ 1. Locate the module	Finds xxx.py or xxx/__init__.py	Standard import mechanism
✅ 2. Read the entire file	Reads all source code in xxx	Needed to compile the module
✅ 3. Compile the code	Translates entire file to bytecode	Python compiles modules before execution
✅ 4. Execute the entire module	Runs all top-level code (function defs, imports, prints, etc.)	To define abc and other objects
✅ 5. Build the module’s namespace	Stores all defined names in xxx.__dict__	This is the module’s own scope
✅ 6. Copy only abc into your scope	Puts abc into your current namespace	That’s what from ... import abc means

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🧠 Key Principles

• Modules are fully executed on import, even if you only import one symbol.

• Python favors explicitness and namespace isolation.

• Function definitions are only known after the file is executed.

• Your local scope only receives what you explicitly ask for.

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Let me know if you'd like a diagram or live code demonstration to see this step-by-step!