def ll_create_node(name, phone): return {'name': name, 'phone': phone, 'next': None} def ll_insert(head, name, phone): if head is None: return ll_create_node(name, phone) current = head while current: if current ['name'] == name: current['phone'] = phone return head if current ['next'] is None: break current = current['next'] current['next'] = ll_create_node(name, phone) return head def ll_find(head, name): current = head while current: if current['name'] == name: return current['phone'] current = current['next'] return None def ll_delete(head, name): if head is None: return None if head['name'] == name: return head['next'] current = head while current['next']: if current['next']['name'] == name: current['next'] = current['next']['next'] return head current = current['next'] return head def ll_list_all(head): items = [] current = head while current: items.append((current['name'], current['phone'])) current = current['next'] return sorted(items, key=lambda x:x[0])