How to use the bioblend.log.error function in bioblend

def _get_volume_placement(self, vol_id):
        """
        Returns the placement of a volume (or None, if it cannot be determined)
        """
        try:
            vol = self.ec2_conn.get_all_volumes(volume_ids=[vol_id])
        except EC2ResponseError as ec2e:
            bioblend.log.error("EC2ResponseError querying for volume {0}: {1}"
                               .format(vol_id, ec2e))
            vol = None
        if vol:
            return vol[0].zone
        else:
            bioblend.log.error("Requested placement of a volume '%s' that does not exist.", vol_id)
            return None

# V2 format.
                    for fs in [fs for fs in pd['filesystems'] if fs.get(
                            'kind', None) == 'volume' and 'ids' in fs]:
                        # All volumes must be in the same zone
                        vol_id = fs['ids'][0]
                        response['placement'] = self._get_volume_placement(
                            vol_id)
                        # No need to continue to iterate through
                        # filesystems, if we found one with a volume.
                        break
            except Exception as exc:
                response['error'] = ("Exception while finding placement for "
                                     "cluster '{0}'. This can indicate malformed "
                                     "instance data. Or that this method is "
                                     "broken: {1}".format(cluster_name, exc))
                bioblend.log.error(response['error'])
                response['placement'] = None
        else:
            bioblend.log.debug("Insufficient info about cluster {0} to get placement."
                               .format(cluster_name))
        return response

# attempt auto allocation of floating IP
                    if rs[0].instances[0].private_ip_address and not public_ip:
                        self.assign_floating_ip(ec2_conn, rs[0].instances[0])
                    cm_url = "http://{dns}/cloud".format(dns=public_ip)
                    # Wait until the CloudMan URL is accessible to return the
                    # data
                    if self._checkURL(cm_url) is True:
                        state['instance_state'] = inst_state
                        state['placement'] = rs[0].instances[0].placement
                    else:
                        state['instance_state'] = 'booting'
                else:
                    state['instance_state'] = inst_state
        except Exception as e:
            err = "Problem updating instance '%s' state: %s" % (instance_id, e)
            bioblend.log.error(err)
            state['error'] = err
        return state

"""
        ms = self.get_machine_status()
        # Check if the machine is running and update IP and state
        self.vm_status = ms.get('instance_state', None)
        self.vm_error = ms.get('error', None)
        public_ip = ms.get('public_ip', None)
        # Update url if we don't have it or is different than what we have
        if not self.url and (public_ip and self.url != public_ip):
            self._set_url(public_ip)
        # See if the cluster has been initialized
        if self.vm_status == 'running' or self.url:
            ct = self.get_cluster_type()
            if ct.get('cluster_type', None):
                self.initialized = True
        if self.vm_error:
            bioblend.log.error(self.vm_error)