title: multipart data POST using python requests: no multipart boundary was found
body: <p>I have a form-data as well as file to be sent in the same POST. For ex, {duration: 2000, file: test.wav}. I saw the many threads here on multipart/form-data posting using python requests. They were useful, especially <a href="https://stackoverflow.com/questions/12592553/python-requests-multipart-http-post?rq=1">this one</a>.</p>
  
  <p>My sample request is as below:</p>
  
  <pre><code>    files = {'file': ('wavfile', open(filename, 'rb'))}
      data = {'duration': duration}
      headers = {'content-type': 'multipart/form-data'}
      r = self.session.post(url, files=files, data=data, headers=headers)
  </code></pre>
  
  <p>But when I execute the above code, I get this error:</p>
  
  <p>5:59:55.338 Dbg 09900  [DEBUG] Resolving exception from handler [null]: org.springframework.web.multipart.MultipartException: Could not parse multipart servlet request; nested exception is org.apache.commons.fileupload.FileUploadException: the request was rejected because no multipart boundary was found.</p>
  
  <p>So my questions are: 1) How can I see the content of the request being sent? Couldn't use wireshark, its not across the network.
  2) why is the boundary missing in the encoded data? Did I miss anything, please point out.</p>