關於傳送資料，Requests提供以下幾種方式

• Streaming Uploads, which allow you to send large streams or files without reading them into memory
• Chunked Transfer Encoding for outgoing and incoming requests.
• Multiple Multipart-Encoded Files

遇到需要傳送大檔案可以考慮使用Streaming Upload，使用方式只要在data提供檔案物件即可
特別注意的是需要以binary mode開啟檔案

with open('massive-body', 'rb') as f:
    requests.post('http://some.url/streamed', data=f)

若要達成Chunked transfer encoding for outgoing的話，使用方式只要在data提供generator即可

def gen():
    yield 'hi'
    yield 'there'

requests.post('http://some.url/chunked', data=gen())

若要達成多檔上傳，使用方式只要在files提供List，內容為(form_field_name, file_info)的Tuple

multiple_files = [
        ('images', ('foo.png', open('foo.png', 'rb'), 'image/png')),
        ('images', ('bar.png', open('bar.png', 'rb'), 'image/png'))]
r = requests.post(url, files=multiple_files)

參考

• Requests-The User Guide-Advanced Usage
• Content Length & Transfer Encoding