curl --request POST \
  --url https://api.deepl.com/v2/write/rephrase \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "text": [
    "this is a example sentence to imprve"
  ]
}
'

{
  "improvements": [
    {
      "detected_source_language": "en",
      "target_language": "en-US",
      "text": "This is a sample sentence to improve."
    }
  ]
}

{
  "message": "<string>",
  "code": "invalid_content_type"
}

{
  "message": "<string>",
  "code": "invalid_content_type"
}

{
  "message": "<string>",
  "code": "invalid_content_type"
}

{
  "message": "Unsupported Content-Type"
}

{
  "message": "<string>",
  "code": "invalid_content_type"
}

{
  "message": "<string>",
  "code": "invalid_content_type"
}

{
  "message": "<string>",
  "code": "invalid_content_type"
}

{
  "message": "<string>",
  "code": "invalid_content_type"
}