C -> POST R -> GET U -> PUT D -> DELETE
.com/user/signup -> post
i/p - name, email
o/p -> user_is, msg
.com/user/delete -> delete
i/p - user_id
o/p -> msg
.com/todo/add -> post
i/p -> user_id, content, due_date, is_completed
o/p -> todo_id, msg
.com/todo/list -> post
i/p -> user_id
o/p -> json list of todo created by user_id
.com/todo/<todo_id> -> get
i/p -> none
o/p -> user_id, todo_content, due_date, is_completed
.com/todo/<todo_id>/update -> post
i/p -> user_id, todo_content, due_date, is_completed
o/p -> todo_id, msg
.com/todo/<todo_id>/delete -> post
i/p -> none
o/p -> msg