def load_header(file: str):
    """Check if the graph is directed, bipartite, weighted."""
    directed, bipartite, weighted = False, False, True
    with open(file, 'r', encoding='utf-8') as f:
        row = f.readline()
        if 'bip' in row:
            bipartite = True
        if 'unweighted' in row:
            weighted = False
        if 'asym' in row:
            directed = True
    return directed, bipartite, weighted