'Returns a dict from the JSON of a REST response.
:param blob: The response from a REST call.
:returns: JSON or None on error.'

def _get_json(self, blob):

    try:
        return blob.json()
    except AttributeError:
        LOG.error('Error    invalid    json:    %s', blob)
    except TypeError as ex:
        LOG.error('Error    TypeError.    %s', ex)
    except scanner.JSONDecodeError as ex:
        LOG.error('Error    JSONDecodeError.    %s', ex)
    LOG.debug('_get_json    blob    %s', blob)
    return None
