import py
html = py.xml.html 

class my(html):
    "a custom style"  
    class body(html.body): 
        style = html.Style(font_size = "120%") 

    class h2(html.h2): 
        style = html.Style(background = "grey")

    class p(html.p): 
        style = html.Style(font_weight="bold")

doc = my.html(
    my.head(), 
    my.body(
        my.h2("hello world"),
        my.p("bold as bold can") 
    )
)
    
print doc.unicode(indent=2) 
