785. Is Graph Bipartite - LeetCode Solution

class Solution:
    def isBipartite(self, graph: List[List[int]]) -> bool:
                     		
        
        visited = {}
        def dfs(node, val):
            visited[node] = val

            for i in range(len(graph[node])):

                if graph[node][i] not in visited:
                    if val == 0:
                        c = 1
                    else:
                        c = 0
                    a = dfs(graph[node][i], c)
                    if not a:
                        return False




                elif val == visited[graph[node][i]]:
                    return False
            return True





        
        for i in range(len(graph)):
            if i not in visited:
                if not dfs(i, 0):
                    return False
        
        return True