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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def dfs_iterative(graph, start, seen):
 """DFS, detect connected component, iterative implementation :param graph: directed graph in listlist or listdict format :param int node: to start graph exploration :param boolean-table seen: will be set true for the connected component containing node. :complexity: `O(|V|+|E|)` """

    seen[start] = True
    to_visit = [start]
    while to_visit:
        node = to_visit.pop()
        for neighbor in graph[node]:
            if not seen[neighbor]:
                seen[neighbor] = True
                to_visit.append(neighbor)