title: Telethon: how to get invite link to private channel?
body: <p>In 1.5 version I did so:</p>
  
  <pre><code>from telethon.tl.functions.channels import ExportInviteRequest
  from telethon.tl.types import InputChannel, InputPeerChannel
  ChannelLink = Client(ExportInviteRequest(
      InputPeerChannel(channel_id=ChannelID,
          access_hash=ChannelHash))).link
  </code></pre>
  
  <p>But it doesn't work now:</p>
  
  <pre><code>ImportError: cannot import name 'ExportInviteRequest'
  </code></pre>
  
  <p>How to do it now?</p>