s.check_valid_email
s.check_valid_url
s.cookie_delete
s.cookie_set
s.echo
s.file_add
s.file_copy
s.file_create
s.file_delete
s.file_exists
s.file_read
s.file_rename
s.file_size
s.file_write
s.folder_content
s.folder_create
s.folder_delete
s.folder_exists
s.folder_rename