def __str__(self):
        return "".join([self.package, self.version or ""])
def __init__(
        self,
        new_item_default_value,
        min_size=0,
        max_size=None,
        item_spacing=ItemBox.ITEM_SPACING,
        max_width=None,
        max_height=None,
        *args,
        **kwargs):
    """
    Parameters: