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{
'ActionController::RoutingError'             => :not_found,
'ActionController::UnknownAction'            => :not_found,
'ActiveRecord::RecordNotFound'               => :not_found,
'ActiveRecord::StaleObjectError'             => :conflict,
'ActiveRecord::RecordInvalid'                => :unprocessable_entity,
'ActiveRecord::RecordNotSaved'               => :unprocessable_entity,
'ActionController::MethodNotAllowed'         => :method_not_allowed,
'ActionController::NotImplemented'           => :not_implemented,
'ActionController::InvalidAuthenticityToken' => :unprocessable_entity