code: func (client *Client) UpdateSpaceManagerByUsername(spaceGUID string, username string) (Warnings, error) {
  	requestBody := updateRoleRequestBody{
  		Username: username,
  	}
  
  	bodyBytes, err := json.Marshal(requestBody)
  	if err != nil {
  		return Warnings{}, err
  	}
  	request, err := client.newHTTPRequest(requestOptions{
  		RequestName: internal.PutSpaceManagerByUsernameRequest,
  		URIParams:   map[string]string{"space_guid": spaceGUID},
  		Body:        bytes.NewReader(bodyBytes),
  	})
  
  	if err != nil {
  		return nil, err
  	}
  
  	response := cloudcontroller.Response{}
  
  	err = client.connection.Make(request, &response)
  
  	return response.Warnings, err
  }
docs: // UpdateSpaceManagerByUsername grants the given username the space manager role.