docs: def forward(self, to_recipients, forward_comment=None):
          # type: (Union[List[Contact], List[str]], str) -> None
          """Forward Message to recipients with an optional comment.
  
          Args:
              to_recipients: A list of :class:`Contacts <pyOutlook.core.contact.Contact>` to send the email to.
              forward_comment: String comment to append to forwarded email.
  
          Examples:
              >>> john = Contact('john.doe@domain.com')
              >>> betsy = Contact('betsy.donalds@domain.com')
              >>> email = Message()
              >>> email.forward([john, betsy])
              >>> email.forward([john], 'Hey John')
          """
          payload = dict()
  
          if forward_comment is not None:
              payload.update(Comment=forward_comment)
  
          # A list of strings can also be provided for convenience. If provided, convert them into Contacts
          if any(isinstance(recipient, str) for recipient in to_recipients):
              to_recipients = [Contact(email=email) for email in to_recipients]
  
          # Contact() will handle turning itself into the proper JSON format for the API
          to_recipients = [contact.api_representation() for contact in to_recipients]
  
          payload.update(ToRecipients=to_recipients)
  
          endpoint = 'https://outlook.office.com/api/v2.0/me/messages/{}/forward'.format(self.message_id)
  
          self._make_api_call('post', endpoint=endpoint, data=json.dumps(payload))