Pymacs Returning (pymacs-python . n)!

[pabloaperezfernandez]

Setup:

1. Emacs 25.2.1 on Windows 10
2. Pymacs 0.25
3. Anaconda Python 3.5.1

I installed Pymacs, and it is running fine. I can run pymacs-eval and pymacs-exec commands successfully from Emacs Lisp. The problemis that some standard Python 3.x statements are returning something strange back to Emacs. In particular, if I run

(pymacs-eval ("import numpy as np;"))
(pymacs-eval "np.max(np.array([[1,1],[2,4]]))")

I get back

(pymacs-python . 1479)

If I run

(np-max (np-array '((1 1) (2 4))))

I get

(pymacs-python . 1479)

This seems to happen whenever I try passing any type of list from Emacs Lisp to Python via Pymacs. Does anybody know what these "(pymacs-python . n)" cons cells mean?