Highlighting Breaks on PyTest #60

I'm using VIM 8.1.1722, MacVim, on MacOSX Mohave 10.14.6.
I installed this plugin with vim-plug, most recent version at the time of writing.

I have a pytest decorator that looks like this:

@pytest.mark.parametrize("sent, count", [("()",0),
                          ("«»",0),
                          ('text test "testing test.', 1)])

and when highlighted in vim using python-syntax, it looks like this:

Everything that comes after this is also badly colored, basically with inverted string highlighting: everything that is a string is highlighted like code and vice versa.