"ImportError: attempted relative import beyond top-level package" when using a stim.extras.RandomDotKinematogram

[chrplr]

Hello,

When calling present_and_wait_keyboard() on a RandomDotKinematogram object, I get:

---

.expyriment/extras/expyriment_stimuli_extras/randomdotkinematogram/_randomdotkinematogram.py", line 251, in present_and_wait_keyboard
    from ... import _internals
ImportError: attempted relative import beyond top-level package

---

Other types of extras.stimuli like GaborPatch, DotCloud, work well.

[chrplr]

Fixed by replacing ... by expyriment on line 251 of _randomdotkinematogram.py

[fladd]

@lindemann09 Can you have a look at this?