def __init__(self, assets_dir=None, requirements_file="requirements.yml"):
        self.assets_dir = assets_dir or Path(".") / "assets"
        self.requirements = GroupedRequirements()
        self.requirements.load(requirements_file)
        self.temp_dir = mkdtemp()
def _init_gui(self):
    self._size_spin_button = gtk.SpinButton(
      gtk.Adjustment(
        value=0,
        lower=self._min_size,
        upper=self._max_size,
        step_incr=1,
        page_incr=10,
      ),
      digits=0)