How to use the scenario.BlockContactScenario function in scenario

def block_contact(self, contact):
        def callback(memberships):
            contact._set_memberships(memberships)
            self.emit('contact-blocked', contact)
        bc = scenario.BlockContactScenario(self._sharing,
                (callback,),
                (self.__common_errback,))
        bc.account = contact.account
        bc.network = contact.network_id
        bc.membership = contact.memberships
        bc()

def block_contact(self, contact, done_cb=None, failed_cb=None):
        def callback(memberships):
            contact._set_memberships(memberships)
            self.__common_callback('contact-blocked', done_cb, contact)
        bc = scenario.BlockContactScenario(self._sharing,
                (callback,),
                (self.__common_errback, failed_cb))
        bc.account = contact.account
        bc.network = contact.network_id
        bc.membership = contact.memberships
        bc()

def block_contact(self, contact, done_cb=None, failed_cb=None):
        def callback(memberships):
            contact._set_memberships(memberships)
            self.__common_callback('contact-blocked', done_cb, contact)
        bc = scenario.BlockContactScenario(self._sharing,
                (callback,),
                (self.__common_errback, failed_cb))
        bc.account = contact.account
        bc.network = contact.network_id
        bc.membership = contact.memberships
        bc()

def block_contact(self, contact, done_cb=None, failed_cb=None):
        def callback(memberships):
            contact._set_memberships(memberships)
            self.__common_callback('contact-blocked', done_cb, contact)
        bc = scenario.BlockContactScenario(self._sharing,
                (callback,),
                (self.__common_errback, failed_cb))
        bc.account = contact.account
        bc.network = contact.network_id
        bc.membership = contact.memberships
        bc()