input: Write a python function to make an API call and return the JSON response.
  assert get_api_data('http://api.example.com/') == {"key": "value"}
  assert get_api_data('http://api.example.com/test') == {"test_key": "test_value"}
  assert get_api_data('http://api.example.com/empty') == {}
output: import requests
  
  def get_api_data(url):
      response = requests.get(url)
      return response.json()