(Quick one, with a very easy fix I will push as a commit but I am raising as an issue in case it is worthy of a changelog note:) the __str__ and __repr__ representations for a Query are missing a closing parenthesis in the current master:
>>> import cf
>>> cf.__version__
'3.11.0'
>>> q = cf.Query('le', 6)
>>> q
<CF Query: (le 6>
>>> print(q)
(le 6
From a git blame it seems like this issue was inadvertently introduced in #216 therefore has been the case since version 3.9.0.