code: def _post(self, path, **kwargs):
          
          # clean kwargs (filter None and empty string)
          clean_kwargs = clean_dict(kwargs)
  
          data = bytes(json.dumps(clean_kwargs), encoding='UTF-8')
          # change content type on post
          self._headers['Content-Type'] = 'application/json'
          api = self._api('%s.json' % path)
          req = request.Request(
              api, headers=self._headers, data=data, method='POST')
          try:
              resp = request.urlopen(req, data).read()
          except urllib.error.HTTPError as e:
              resp = e.fp.read()
          # reset content type
          self._headers['Content-Type'] = 'text/json'
          return json.loads(resp.decode())
docs: return a dict.