'Test that posting a bookmark for a block that does not exist returns a 400.'

def test_post_bookmark_for_non_existing_block(self):

    response = self.send_post(client=self.client, url=reverse('bookmarks'), data={'usage_id': 'i4x://arbi/100/html/340ef1771a094090ad260ec940d04a21'}, expected_status=400)
    self.assertEqual(response.data['user_message'], u'An    error    has    occurred.    Please    try    again.')
    self.assertEqual(response.data['developer_message'], u'Block    with    usage_id:    i4x://arbi/100/html/340ef1771a094090ad260ec940d04a21    not    found.')
