def _get_texture(self, filename):
        """
        Returns the texture associated with the filename. Loads it from
        resources if it haven't done before.
        """
        if self._textures not in filename:
            texture = self._loader.texture(filename)
            self._textures[filename] = texture
        return self._textures[filename]
dataset/ETHPy150Open jorgecarleitao/pyglet-gui/pyglet_gui/theme/parsers.py/TextureParser._get_texture/swapped operands of `not in`