input: Write a python function to send a GET request to a given URL and return the response text.
  assert get_response_text("https://example.com") == "<!doctype html><html>...</html>"
  assert get_response_text("https://jsonplaceholder.typicode.com/posts/1") == '{"userId": 1, "id": 1, "title": "..."...}'
output: def get_response_text(url):
      import requests
      response = requests.get(url)
      return response.text