'Show that a user can iterate over a list of gist files.'

def test_files(self):

    cassette_name = self.cassette_name('files')
    with self.recorder.use_cassette(cassette_name):
        gists = self.gh.gists_by('sigmavirus24')
        assert (gists is not None)
        for gist in gists:
            files = gist.files()
            for _file in files:
                assert isinstance(_file, github3.gists.file.GistFile)
