code: def init_storage_dir(storage_dir):
      
      storage_path = FilePath(storage_dir)
  
      # Create the default wildcard certificate if it doesn't already exist
      default_cert_path = storage_path.child('default.pem')
      if not default_cert_path.exists():
          default_cert_path.setContent(generate_wildcard_pem_bytes())
  
      # Create a directory for unmanaged certs. We don't touch this again, but it
      # needs to be there and it makes sense to create it at the same time as
      # everything else.
      unmanaged_certs_path = storage_path.child('unmanaged-certs')
      if not unmanaged_certs_path.exists():
          unmanaged_certs_path.createDirectory()
  
      # Store certificates in a directory inside the storage directory, so
      # HAProxy will read just the certificates there.
      certs_path = storage_path.child('certs')
      if not certs_path.exists():
          certs_path.createDirectory()
  
      return storage_path, certs_path
docs: Initialise the storage directory with the certificates directory and a
      default wildcard self-signed certificate for HAProxy.
  
      :return: the storage path and certs path