code: def remove_user_from_group(group, role, email):
      
      uri = "groups/{0}/{1}/{2}".format(group, role, email)
      return __delete(uri)
docs: Remove a user from a group the caller owns
  
      Args:
          group (str): Group name
          role (str) : Role of user for group; either 'member' or 'admin'
          email (str): Email of user or group to remove
      
      Swagger:
          https://api.firecloud.org/#!/Groups/removeUserFromGroup