def line(svg, node, font_size):
    """Draw line tag."""
    x1, y1 = svg.point(node.get('x1'), node.get('y1'), font_size)
    x2, y2 = svg.point(node.get('x2'), node.get('y2'), font_size)
    svg.stream.move_to(x1, y1)
    svg.stream.line_to(x2, y2)
    angle = atan2(y2 - y1, x2 - x1)
    node.vertices = [(x1, y1), (pi - angle, angle), (x2, y2)]
Draw line tag.
weasyprint/svg/shapes.py