docs: def approle_token(vault_client, role_id, secret_id):
      """Returns a vault token based on the role and seret id"""
      resp = vault_client.auth_approle(role_id, secret_id)
      if 'auth' in resp and 'client_token' in resp['auth']:
          return resp['auth']['client_token']
      else:
          raise aomi.exceptions.AomiCredentials('invalid approle')