input: Write a python function to fetch data from a given URL and return the JSON response.
  assert fetch_data('https://coronavirus-19-api.herokuapp.com/') is not None
  assert isinstance(fetch_data('https://coronavirus-19-api.herokuapp.com/'), dict)
output: import requests
  
  def fetch_data(url):
      response = requests.get(url)
      return response.json()