在Python3中实现呼吸优先搜索(如何将'Set‘转换为'Dictionary’

from collections import deque

def breath_first_search(graph, start, target):
    queue = deque()
    queue.append(start)
    
    visited = set()
    visited.add(start)
    
    parent = {}
    parent[start] = None
    
    while queue:
        current_node = queue.popleft()
        
        if current_node == target:
            path = []
            while current_node is not None:
                path.append(current_node)
                current_node = parent[current_node]
            path.reverse()
            return path
        
        for neighbor in graph[current_node]:
            if neighbor not in visited:
                queue.append(neighbor)
                visited.add(neighbor)
                parent[neighbor] = current_node
    
    return None

my_set = {'a', 'b', 'c'}
my_dict = {value: index for index, value in enumerate(my_set)}