code: def _init_request_urls(self, api_urls):
          
          if not isinstance(api_urls, (str, list, tuple)):
              raise TypeError('api_urls needs to be string or iterable!')
  
          if isinstance(api_urls, str):
              api_urls = (api_urls,)
  
          api_urls = list(api_urls)
  
          for url in api_urls:
              if not url.startswith('http://') and \
                 not url.startswith('https://'):
                  raise ValueError(('URL "%s" contains an invalid or missing'
                                   ' scheme' % (url)))
  
          return list(api_urls)
docs: Returns a list of the API URLs.