code: private void populateRequestHeaders(HttpRequestBase httpRequest, Map<String, String> requestHeaders) {
  
          Set<String> keySet = requestHeaders.keySet();
          Iterator<String> keySetIterator = keySet.iterator();
          while (keySetIterator.hasNext()) {
              String key = keySetIterator.next();
              String value = requestHeaders.get(key);
              httpRequest.addHeader(key, value);
          }
  
          PropertyHelper propertyHelper = PropertyHelper.getInstance();
          String requestSource = propertyHelper.getRequestSource() + propertyHelper.getVersion();
          if(propertyHelper.getRequestSourceHeader() != null){
              httpRequest.addHeader(propertyHelper.getRequestSourceHeader(), requestSource);
          }
  
      }
docs: Method to populate the HTTP request headers by reading it from the requestHeaders Map
  
  @param httpRequest the http request
  @param requestHeaders the request headers