What minimum should a person know before saying "I know Python"

[Aseem Bansal]

I started Python 4 months ago. Largely self-study with use of Python documentation, stackoverflow and google. I was thinking what is the minimum that I must know before I can say that I know Python?

I come from a C background which is comparatively smaller. But as Python is comparatively much larger what minimum should I know?

Just a general question not for a specific purpose.