code: def _add_bearer_token(self, uri, http_method='GET', body=None,
                            headers=None, token_placement=None):
          
          if token_placement == AUTH_HEADER:
              headers = tokens.prepare_bearer_headers(self.access_token, headers)
  
          elif token_placement == URI_QUERY:
              uri = tokens.prepare_bearer_uri(self.access_token, uri)
  
          elif token_placement == BODY:
              body = tokens.prepare_bearer_body(self.access_token, body)
  
          else:
              raise ValueError("Invalid token placement.")
          return uri, headers, body
docs: Add a bearer token to the request uri, body or authorization header.