curl --request POST \
  --url https://resale.api.sandbox.bango.com/v1/echo/{echoString} \
  --header 'x-api-key: <api-key>'

const options = {method: 'POST', headers: {'x-api-key': '<api-key>'}};

fetch('https://resale.api.sandbox.bango.com/v1/echo/{echoString}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://resale.api.sandbox.bango.com/v1/echo/{echoString}"

headers = {"x-api-key": "<api-key>"}

response = requests.post(url, headers=headers)

print(response.text)

{
  "responseCode": "OK",
  "responseMessage": "Success",
  "echo": "echoString"
}

{
  "responseCode": "INTERNAL_ERROR",
  "responseMessage": null,
  "metadata": {
    "responseMessageFrom": "BANGO"
  }
}

{
  "responseCode": "SERVICE_UNAVAILABLE",
  "responseMessage": null,
  "metadata": {
    "responseMessageFrom": "BANGO"
  }
}