dictionary changed size during iteration error on page refresh

[aFraley]

We are getting a dictionary changed size during iteration error on every other page refresh.
Environment:

Request Method: GET
Request URL: http://localhost:8000/pdf/

Django Version: 1.11.1
Python Version: 3.6.1
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'rest_framework',
 'rest_framework.authtoken',
 'corsheaders',
 'hardcopy',
 'accounts',
 'projects',
 'api']
Installed Middleware:
['corsheaders.middleware.CorsMiddleware',
 'djdev_panel.middleware.DebugMiddleware',
 'django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware']



Traceback:

File "/Users/alan/dev/python/undertaker/venv/lib/python3.6/site-packages/django/core/handlers/exception.py" in inner
  41.             response = get_response(request)

File "/Users/alan/dev/python/undertaker/venv/lib/python3.6/site-packages/django/core/handlers/base.py" in _get_response
  178.             response = middleware_method(request, callback, callback_args, callback_kwargs)

File "/Users/alan/dev/python/undertaker/venv/lib/python3.6/site-packages/djdev_panel/middleware.py" in process_view
  143.         for key in VIEW_METHOD_DATA.keys():

Exception Type: RuntimeError at /pdf/
Exception Value: dictionary changed size during iteration```

[ckinsey]

This was fixed in a previous release, along with a couple of other Python 3 related bugs.