missing pyb

Hello, how do I install **pyb**?

I get this error

    >>> import upip
    >>> upip.install('pyb')
    Installing to: /lib/
    Warning: pypi.python.org SSL certificate is not validated
    Error installing 'pyb': , packages may be partially installed

Thanks

(I'm using micropython on a ESP8266 NodeMCU Amica)
