serverless-python-requirements: Problem with pip cache permissions

I’m getting some issues with the docker based build and file permissions inside of the container. Any ideas?

Here are the configuration options:

custom:
  pythonRequirements:
    zip: true
    dockerizePip: true

And here is the error message I’m getting:

Serverless: Removing Python requirements helper...
Serverless: Adding Python requirements helper...
Serverless: Parsing Python requirements.txt
Serverless: Installing required Python packages for runtime python2.7...
Serverless: Docker Image: lambci/lambda:build-python2.7

  Error --------------------------------------------------

  The directory '/root/.cache/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/root/.cache' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Exception:
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/pip/basecommand.py", line 215, in main
    status = self.run(options, args)
  File "/usr/local/lib/python2.7/site-packages/pip/commands/install.py", line 324, in run
    requirement_set.prepare_files(finder)
  File "/usr/local/lib/python2.7/site-packages/pip/req/req_set.py", line 380, in prepare_files
    ignore_dependencies=self.ignore_dependencies))
  File "/usr/local/lib/python2.7/site-packages/pip/req/req_set.py", line 554, in _prepare_file
    require_hashes
  File "/usr/local/lib/python2.7/site-packages/pip/req/req_install.py", line 281, in populate_link
    self.link = self._wheel_cache.cached_wheel(self.link, self.name)
  File "/usr/local/lib/python2.7/site-packages/pip/wheel.py", line 68, in cached_wheel
    self._cache_dir, link, self._format_control, package_name)
  File "/usr/local/lib/python2.7/site-packages/pip/wheel.py", line 129, in cached_wheel
    wheel_names = os.listdir(root)
OSError: [Errno 13] Permission denied: '/root/.cache/wheels/44/56/6f/d5ac6dce9c887d96df2cd7b27ed0a6dd9357ef82b951ebb777'


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