'Delete a firewall rule
:param  firewall_rule: The firewall rule to delete.
:type:  firewall_rule: :class:`ProfitBricksFirewallRule`
:rtype  ``bool``'

def ex_delete_firewall_rule(self, firewall_rule):

    action = firewall_rule.href
    self.connection.request(action=action, method='DELETE', with_full_url=True)
    return True
