def install(h, pip, groups, save, save_dev, packages):
    """Install a pip or bower package."""
    if groups:
        groups = [text_type.strip(group) for group in groups.split(",")]
    else:
        groups = h.requirements.keys()

    if not packages:
        for group in groups:
            if group not in h.requirements:
                warning("{} not in requirements".format(group))
                continue
            install = (h.install_bower if group.startswith("bower")
                       else h.install_pip)
            for requirement in h.requirements[group]:
                install(str(requirement), save=False, save_dev=False)
    if pip:
        for package in packages:
            h.install_pip(package, save=save, save_dev=save_dev)
    else:
        for package in packages:
            h.install_bower(package, save=save, save_dev=save_dev)
def draw():
    global theta
    context.clearRect(0, 0, canvas.width, canvas.height)
    line1.drawMe(context)
    line2.drawMe(context)
    line3.drawMe(context)
    #triangle1.drawMe(context)
    #triangle2.drawMe(context)
    theta += dx
    p2.x = p1.x + line1.length*math.cos(theta*degree)
    p2.y = p1.y - line1.length*math.sin(theta*degree)
    p3.x, p3.y = triangle2.setPPSS(p2,p4,link2_len,link3_len)
    p1.tag(context)