code: def uri(host='localhost', port=5432, dbname='postgres', user='postgres',
          password=None):
      
      if port:
          host = '%s:%s' % (host, port)
      if password:
          return 'postgresql://%s:%s@%s/%s' % (user, password, host, dbname)
      return 'postgresql://%s@%s/%s' % (user, host, dbname)
docs: Return a PostgreSQL connection URI for the specified values.
  
      :param str host: Host to connect to
      :param int port: Port to connect on
      :param str dbname: The database name
      :param str user: User to connect as
      :param str password: The password to use, None for no password
      :return str: The PostgreSQL connection URI