input: Write a python function to get weather information for a given city using an API call.
  assert get_weather_info('London')['temp'] is not None
  assert get_weather_info('New York')['humidity'] is not None
  assert get_weather_info('Tokyo')['wind_speed'] is not None
output: def get_weather_info(city):
      import requests
  
      API_KEY = 'your_api_key_here'  # Replace with your actual API key
      BASE_URL = 'http://api.openweathermap.org/data/2.5/weather'
  
      params = {
          'q': city,
          'appid': API_KEY,
          'units': 'metric'
      }
  
      response = requests.get(BASE_URL, params=params)
      weather_data = response.json()
  
      if response.status_code == 200:
          return {
              'temp': weather_data['main']['temp'],
              'humidity': weather_data['main']['humidity'],
              'wind_speed': weather_data['wind']['speed']
          }
      else:
          return {'error': 'City not found or API request failed'}