title: Learning asyncio: "coroutine was never awaited" warning error
body: <p>I am trying to learn to use asyncio in Python to optimize scripts.
  My example returns a <code>coroutine was never awaited</code> warning, can you help to understand and find how to solve it? </p>
  
  <pre><code>import time 
  import datetime
  import random
  import asyncio
  
  import aiohttp
  import requests
  
  def requete_bloquante(num):
      print(f'Get {num}')
      uid = requests.get("https://httpbin.org/uuid").json()['uuid']
      print(f"Res {num}: {uid}")
  
  def faire_toutes_les_requetes():
      for x in range(10):
          requete_bloquante(x)
  
  print("Bloquant : ")
  start = datetime.datetime.now()
  faire_toutes_les_requetes()
  exec_time = (datetime.datetime.now() - start).seconds
  print(f"Pour faire 10 requêtes, ça prend {exec_time}s\n")
  
  async def requete_sans_bloquer(num, session):
      print(f'Get {num}')
      async with session.get("https://httpbin.org/uuid") as response:
          uid = (await response.json()['uuid'])
      print(f"Res {num}: {uid}")
  
  async def faire_toutes_les_requetes_sans_bloquer():
      loop = asyncio.get_event_loop()
      with aiohttp.ClientSession() as session:
          futures = [requete_sans_bloquer(x, session) for x in range(10)]
          loop.run_until_complete(asyncio.gather(*futures))
      loop.close()
      print("Fin de la boucle !")
  
  print("Non bloquant : ")
  start = datetime.datetime.now()
  faire_toutes_les_requetes_sans_bloquer()
  exec_time = (datetime.datetime.now() - start).seconds
  print(f"Pour faire 10 requêtes, ça prend {exec_time}s\n")
  </code></pre>
  
  <p>The first <em>classic</em> part of the code runs correctly, but the second half only produces: </p>
  
  <pre><code>synchronicite.py:43: RuntimeWarning: coroutine 'faire_toutes_les_requetes_sans_bloquer' was never awaited
  </code></pre>