According to http://ogp.me/ description is not required.

[LeResKP]

Also fix the example.

Please note the example from the readme was not working

HTML = """
...
... <title>The Rock (1996)</title>
...
...
...
...
... ...
...
... ...
... """
import opengraph
movie = opengraph.OpenGraph()
movie.parser(HTML)
movie.is_valid()
False
movie.required_attrs
['title', 'type', 'image', 'url', 'description']
movie.required_attrs.pop(-1)
'description'
movie.is_valid()
True