What prevents you from putting it in Subject "as is" ?

>
>I send emails through a rest API.
>
>In the subject I want to send characters with an accent. For example I want to send the following text as a subject.
>
>"L'été est de retour" which translates in english to "The summer is back" (For you curious people).
>
>Not a big deal in "html_body" because the string I will add will be
>
>L'& #233 t & #233 est de retour
>
>Anybody can tell me how I can add accentuated characters in "subject" field in the json construct?
>
>

>{
>    "api_key": "api-40246460336B11E6AA53F23C91285F72",
>    "to": ["Test Person <test@example.com>"],
>    "sender": "Test Persons Friend <test2@example.com>",
>    "subject": "Hello Test Person",
>    "text_body": "You're my favorite test person ever",
>    "html_body": "<h1>You're my favorite test person ever</h1>",
>    "custom_headers": [
>      {
>        "header": "Reply-To",
>        "value": "Actual Person <test3@example.com>"
>      }
>    ],
>    "attachments": [
>        {
>            "filename": "test.pdf",
>            "fileblob": "--base64-data--",
>            "mimetype": "application/pdf"
>        },
>        {
>            "filename": "test.txt",
>            "fileblob": "--base64-data--",
>            "mimetype": "text/plain"
>        }
>    ]
>}
>

>
>Thank you.