title: Python built-in AsyncIO implementations?
body: <p>I have been started to understand AsyncIO, which basically "pauses" a function and goes to the next one when it needs to do non-blocking actions like make a web request or open a file (Are there others?)</p>
  
  <p>But then, where are the built-in implementations of an async web request or an async file opening? Isn't AsyncIO just a concept without these? </p>
  
  <p>I have only found external libraries that implement them.</p>
  
  <p>Or is this the intended case? If so how am I supposed to implement my own async request/file library?</p>