input: Write a Python function to get pageview data for the 'Main_Page' of Wikipedia over the last 30 days and store it in a dictionary.
  assert isinstance(get_pageview_data_for_last_30_days(), dict)
  assert all(isinstance(v, int) for v in get_pageview_data_for_last_30_days().values())
  assert len(get_pageview_data_for_last_30_days()) == 30
output: import requests
  from datetime import datetime, timedelta
  
  def get_pageview_data_for_last_30_days():
      end_date = datetime.utcnow()
      start_date = end_date - timedelta(days=30)
      end_date_str = end_date.strftime('%Y%m%d')
      start_date_str = start_date.strftime('%Y%m%d')
  
      url = f'https://wikimedia.org/api/rest_v1/metrics/pageviews/per-article/en.wikipedia/all-access/all-agents/Main_Page/daily/{start_date_str}/{end_date_str}'
      response = requests.get(url)
      data = response.json()
  
      pageviews = {}
      for item in data['items']:
          date_str = item['timestamp'][:8]
          pageviews[date_str] = item['views']
  
      return pageviews