title: "Error parsing JSON" when using Spotify API
body: <p>I am learning Python and I am trying to create a playlist using the Spotify web api but get a http 400 error: Error parsing json. I guess it has to do with an incorrect variable type in the token but I am having a really hard time debugging it as I can't figure out a way to see the post request in raw format.</p>
  
  <p>Posting through the API requires authorizing and this is the script I've created for that:</p>
  
  <pre><code>import requests
  import base64
  requests.packages.urllib3.disable_warnings()
  
  client_id = 'ID'
  client_secret = 'SECRET'
  redirect_uri = 'http://spotify.com/'
  scope = 'playlist-modify-private playlist-read-private'
  
  def request_token():
  
      #  1. Your application requests authorization
      auth_url = 'https://accounts.spotify.com/authorize'
      payload = {'client_id': client_id, 'response_type':'code','redirect_uri':redirect_uri}
      auth = requests.get(auth_url,params = payload)
      print '\nPlease go to this url to authorize ', auth.url
  
      #  2. The user is asked to authorize access within the scopes
      #  3. The user is redirected back to your specified URI
      resp_url = raw_input('\nThen please copy-paste the url you where redirected to: ')
      resp_code= resp_url.split("?code=")[1].split("&amp;")[0]
  
      #  4. Your application requests refresh and access tokens
      token_url = 'https://accounts.spotify.com/api/token'
      payload = {'redirect_uri': redirect_uri,'code': resp_code, 'grant_type': 'authorization_code','scope':scope}
      auth_header = base64.b64encode(client_id + ':' + client_secret)
      headers = {'Authorization': 'Basic %s' % auth_header}
      req = requests.post(token_url, data=payload, headers=headers, verify=True)
      response = req.json()
  
      return response
  </code></pre>
  
  <p>This is the function actually trying to create the playlist using the authorization token (<em>import authorizer</em> is the function above):</p>
  
  <pre><code>import requests
  import authorizer
  
  def create_playlist(username, list_name):
      token = authorizer.request_token()
      access_token = token['access_token']
      auth_header = {'Authorization': 'Bearer {token}'.format(token=access_token), 'Content-Type': 'application/json'}
      api_url = 'https://api.spotify.com/v1/users/%s/playlists' % username
      payload = {'name': list_name, 'public': 'false'}
      r = requests.post(api_url, params=payload, headers=auth_header)
  </code></pre>
  
  <p>But whatever I try it only leads to a 400 error. Can anyone please point out my error here?</p>