Implement a class named HeadingParser

that

can be used to parse an HTML document, and retrieve and print all the

headings in the document. You should implement your class as a subclass

of HTMLParser, defined in Standard Library module html.parser. When fed a string

containing HTML code, your class should print the headings, one per line and in

the order in which they appear in the document. Each heading should be

indented as follows: an h1 heading should have indentation 0, and h2

heading should have indentation 1, etc. Test your implementation using

w3c.html.

>>> infile = open('w3c.html')

>>> content = infile.read()

>>>

infile.close()

>>> hp = HeadingParser()

>>>

hp.feed(content)

W3C

Mission

Principles