code: func (c *Manager) AddLibraryItemFileFromURI(
  	ctx context.Context,
  	sessionID, fileName, uri string) (*UpdateFileInfo, error) {
  
  	n, fingerprint, err := GetContentLengthAndFingerprint(ctx, uri)
  	if err != nil {
  		return nil, err
  	}
  
  	info, err := c.AddLibraryItemFile(ctx, sessionID, UpdateFile{
  		Name:       fileName,
  		SourceType: "PULL",
  		Size:       &n,
  		SourceEndpoint: &SourceEndpoint{
  			URI:                      uri,
  			SSLCertificateThumbprint: fingerprint,
  		},
  	})
  	if err != nil {
  		return nil, err
  	}
  
  	return info, c.CompleteLibraryItemUpdateSession(ctx, sessionID)
  }
docs: // AddLibraryItemFileFromURI adds a file from a remote URI.