code: def import_app_credentials(filename=CREDENTIALS_FILENAME):
      
      with open(filename, 'r') as config_file:
          config = safe_load(config_file)
  
      client_id = config['client_id']
      client_secret = config['client_secret']
      redirect_url = config['redirect_url']
  
      config_values = [client_id, client_secret, redirect_url]
  
      for value in config_values:
          if value in DEFAULT_CONFIG_VALUES:
              exit('Missing credentials in {}'.format(filename))
  
      credentials = {
          'client_id': client_id,
          'client_secret': client_secret,
          'redirect_url': redirect_url,
          'scopes': set(config['scopes']),
      }
  
      return credentials
docs: Import app credentials from configuration file.
  
      Parameters
          filename (str)
              Name of configuration file.
  
      Returns
          credentials (dict)
              All your app credentials and information
              imported from the configuration file.