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Python by Contrast

Async by contrast

Lesson 4 of 5

Python's async mirrors JS almost keyword for keyword — but you start the event loop yourself, coroutines are lazy, and one blocking call freezes everything.

What you'll learn

  • Start an event loop explicitly with asyncio.run
  • Map async def, await and gather onto async, await and Promise.all
  • Understand why a blocking sync call freezes the whole loop
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