def parse_size(root):
    """Parse the width and height of the image out of the root node.

    Args:
    ----
        root: xml.etree.ElementTree.Element

    Output:
    ------
        width: str
        height str
    """

    size_node = root.find('size')
    width = size_node.find('width').text
    height = size_node.find('height').text

    return width, height