title: What is the request header by default in python requests
body: <p>I am using <a href="http://docs.python-requests.org/en/master/" rel="noreferrer">requests</a> to POST my data to a URL. I need to know what is the header that is sending by my request?</p>
  
  <pre><code>import requests
  conf_json = {"key_1": "value_1", "key_2": "value_2"}                    
  r = requests.post(API-URL, json=conf_json)
  </code></pre>
  
  <p>I can get response header by <code>r.headers</code>, but I need request header and I don't know how I should get it. can you please guide me?</p>