Graph Valid Tree

class Solution:
    """
    @param n: An integer
    @param edges: a list of undirected edges
    @return: true if it's a valid tree, or false
    """
    def valid_tree(self, n, edges):
        parents = [i for i in range(n)]

        def find_root(node):
            while parents[node] != node:
                node = parents[node]
            return node

        for u, v in edges:
            ur = find_root(u)
            vr = find_root(v)

            if ur == vr:
                return False

            parents[ur] = vr

        return len(edges) == n - 1