GET http://localhost:3000/students

###
GET http://localhost:3000/students/-3

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POST http://localhost:3000/students
Content-Type: application/json

{
  "name": "Max",
  "course": "Italien"
}

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PATCH http://localhost:3000/students/-1
Content-Type: application/json

{
  "name": "Annalisa",
  "course": "Informatik"
}

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DELETE http://localhost:3000/students/-2