code: func (c *Client) CollaboratorInfo(appIdentity string, collaboratorIdentity string) (*Collaborator, error) {
  	var collaborator Collaborator
  	return &collaborator, c.Get(&collaborator, "/apps/"+appIdentity+"/collaborators/"+collaboratorIdentity)
  }
docs: // Info for existing collaborator.
  //
  // appIdentity is the unique identifier of the Collaborator's App.
  // collaboratorIdentity is the unique identifier of the Collaborator.