old_contents: # Webhooks for external integrations.
  from typing import Text
  
  from django.http import HttpRequest, HttpResponse
  
  from zerver.decorator import api_key_only_webhook_view
  from zerver.lib.actions import check_send_stream_message
  from zerver.lib.request import REQ, has_request_variables
  from zerver.lib.response import json_success
  from zerver.models import UserProfile
  
  @api_key_only_webhook_view("Heroku")
  @has_request_variables
  def api_heroku_webhook(request, user_profile, stream=REQ(default="heroku"),
                         head=REQ(), app=REQ(), user=REQ(), url=REQ(), git_log=REQ()):
      # type: (HttpRequest, UserProfile, Text, Text, Text, Text, Text, Text) -> HttpResponse
      template = "{} deployed version {} of [{}]({})\n> {}"
      content = template.format(user, head, app, url, git_log)
  
      check_send_stream_message(user_profile, request.client, stream, app, content)
      return json_success()
  
new_contents: # Webhooks for external integrations.
  from typing import Text
  
  from django.http import HttpRequest, HttpResponse
  
  from zerver.decorator import api_key_only_webhook_view
  from zerver.lib.actions import check_send_stream_message
  from zerver.lib.request import REQ, has_request_variables
  from zerver.lib.response import json_success
  from zerver.models import UserProfile
  
  @api_key_only_webhook_view("Heroku")
  @has_request_variables
  def api_heroku_webhook(request: HttpRequest, user_profile: UserProfile,
                         stream: Text=REQ(default="heroku"), head: Text=REQ(),
                         app: Text=REQ(), user: Text=REQ(),
                         url: Text=REQ(), git_log: Text=REQ()) -> HttpResponse:
      template = "{} deployed version {} of [{}]({})\n> {}"
      content = template.format(user, head, app, url, git_log)
  
      check_send_stream_message(user_profile, request.client, stream, app, content)
      return json_success()
  
subject: Use Python 3 syntax for typing in heroku/view.py.