What does a . in an import statement in Python mean?

default one dot in your current folder, when you want to go parent folder you can do like this, my python version 3.6.3

The dot in the module name is used for relative module import (see here and here, section 6.4.2).

You can use more than one dot, referring not to the curent package but its parent(s). This should only be used within packages, in the main module one should always use absolute module names.

That's the syntax for explicit relative imports. It means import from the current package.