from grab import Grab
g = Grab()
g.setup(charset='UTF-8', timeout=45, connect_timeout=35)
g.go('http://www.youtube.com/channel_ajax?action_more_single_playlist_videos=1&page=2&list_id=UUpwvZwUam-URkxB7g4USKpg')

js=json.loads(resp.body)

js['html']

json_gata = g.responce.body
json_html = json_gata.json.loads['html']

>>> g.response.body.json
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'str' object has no attribute 'json'

data = g.response.body
json_data = json.loads(data)
json.loads(data)['html']