Specifying file mime type for multipart requests using python requests module

I'm unable to specify the mime type of the files sent as part of multipart/form-data requests using the python requests module.

I believe the relevant code is here: https://github.com/Kong/httpsnippet/blob/master/src/targets/python/requests/client.ts#L82

I was thinking we could support it by making a change like so:

if (p.fileName) {
  if (p.mimeType) {
     files[p.name] = `('${p.fileName}', open('${p.fileName}', 'rb'), '${p.mimeType}')`;
  } else {
     // current behaviour
     files[p.name] = `open('${p.fileName}', 'rb')`;
  }
  hasFiles = true;
} else {
  payload[p.name] = p.value;
  hasPayload = true;
}

从 src/targets/python/requests/client.ts 约第 82 行开始，检查 Python requests 代码片段中 multipart 文件是如何组装的。将当前的文件处理方式与拟议的 MIME-type 行为进行比较，然后检查附近的测试或 target fixtures（如果存在）。当带有 MIME-type 的 file 参数生成所要求的 multipart 元组，同时现有的文件和 payload 处理保持不变时，即表示完成。