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All your php classes must have namespace Apps\TodoList, This help the autoloader knows where to load scripts.
There is a rule of naming things: if you want to create a controller named Index, you should name the php file as IndexController.php; in Start.php, the route should be book.index" the template file should be index.html.php (the first part of template file's name must be the same as the last part of the route - index)
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