old_contents: import requests
  import pydash
  
  BASE_URL = 'https://android.clients.google.com/fdfe/'
  CLIENT_ID = 'am-google'
  
  class Client(object):
      def __init__(self, android_id, auth_token, language='en-US', **kwargs):
          self.android_id = android_id
          self.auth_token = auth_token
          self.language = language
          self.request_options_base = kwargs
  
      def request(self, endpoint, **kwargs):
          request_options_common = {
                  'url': BASE_URL + endpoint,
                  'headers': {
                      'Accept-Language': self.language,
                      'Authorization': 'GoogleLogin auth=' + self.auth_token,
                      'X-DFE-Device-Id': self.android_id,
                      'X-DFE-Client-Id': CLIENT_ID,
                      'User-Agent': (
                          'Android-Finsky/5.5.12 (api=3,versionCode=80351200,' +
                          'sdk=18,device=x86,hardware=android_x86,' +
                          'product=android_x86,platformVersionRelease=4.3,' +
                          'model=VirtualBox,buildId=JSS15J,isWideScreen=0)'),
                      },
                  'verify': False,
                  }
          options = pydash.merge({},
                  self.request_options_base,
                  request_options_common,
                  kwargs,
                  )
          return requests.get(**options)
  
      def details(self, doc):
          return self.request('details', params={'doc': doc})
  
new_contents: import requests
  import pydash
  
  BASE_URL = 'https://android.clients.google.com/fdfe/'
  CLIENT_ID = 'am-google'
  
  class Client(object):
      def __init__(self, android_id, auth_token, language='en-US', **kwargs):
          self.android_id = android_id
          self.auth_token = auth_token
          self.language = language
          self.request_options_base = kwargs
  
      def request(self, endpoint, **kwargs):
          request_options_common = {
                  'url': BASE_URL + endpoint,
                  'headers': {
                      'Accept-Language': self.language,
                      'Authorization': 'GoogleLogin auth=' + self.auth_token,
                      'X-DFE-Device-Id': self.android_id,
                      'X-DFE-Client-Id': CLIENT_ID,
                      'User-Agent': (
                          'Android-Finsky/5.5.12 (api=3,versionCode=80351200,' +
                          'sdk=18,device=x86,hardware=android_x86,' +
                          'product=android_x86,platformVersionRelease=4.3,' +
                          'model=VirtualBox,buildId=JSS15J,isWideScreen=0)'),
                      },
                  'verify': False,
                  }
          options = pydash.merge({},
                  self.request_options_base,
                  request_options_common,
                  kwargs,
                  )
          return requests.get(**options)
  
      def details(self, doc):
          return self.request('details',
                  params={
                      'doc': doc,
                      },
                  headers={
                      'X-DFE-No-Prefetch': 'true',
                      })
  
subject: Use 'X-DFE-No-Prefetch': 'true'