curl --request GET \
  --url https://app.pennylane.com/api/external/v2/purchase_requests/{id} \
  --header 'Authorization: Bearer <token>'

{
  "id": 1,
  "purchase_request_number": "PR20230001",
  "supplier": {
    "id": 2,
    "url": "https://app.pennylane.com/api/external/v2/suppliers/2"
  },
  "requester": {
    "id": 3
  },
  "reviewer": {
    "id": 4
  },
  "delivery_address": {
    "address": "8 rue de la paix",
    "postal_code": 75002,
    "city": "Paris",
    "country_alpha2": "FR"
  },
  "status": "to_be_validated",
  "currency": "EUR",
  "reason": "I need a computer to be able to create purchase requests",
  "estimated_delivery_date": "2023-12-31",
  "amount": "1234.56",
  "currency_amount": "1234.56",
  "currency_amount_before_tax": "1200.23",
  "exchange_rate": "1.0",
  "currency_tax": "34.33",
  "tax": "34.33",
  "purchase_order": {
    "filename": "Bon-de-commande_n°2025-1.pdf",
    "url": "https://www.pennylane.com/Bon-de-commande_n%C2%B02025-1.pdf"
  },
  "categories": {
    "url": "https://app.pennylane.com/api/external/v2/purchase_requests/42/categories"
  },
  "matched_invoices": {
    "items": [
      {
        "id": 42,
        "url": "https://app.pennylane.com/api/external/v2/purchase_requests/42/matched_invoices"
      }
    ]
  },
  "created_at": "2023-08-30T10:08:08.146343Z",
  "updated_at": "2023-08-30T10:08:08.146343Z"
}