Load Python standard module from Modular Mojo

Question

I've just got access to new Modular's Mojo Playground. If you haven't seen Mojo yet, it builds up on Python,and promisses massive speed up improvements.

From the available information and docs, it claims to be fully compatible with Python syntax and modules.

However, from the Playground notebook, I can't seem to be able to load any module from Python:

In:
import os
import time
import sys
import numpy

Out:
error: Expression [1]:5:8: unable to locate module 'os'
import os
       ^

error: Expression [1]:7:8: unable to locate module 'time'
import time
       ^

error: Expression [1]:6:8: unable to locate module 'sys'
import sys
       ^

error: Expression [1]:8:8: unable to locate module 'numpy'
import numpy
       ^