Two more zip instances

    # Get the node features

    idx_nodes = [(a.GetIdx(), atom_features(a)) for a in mol.GetAtoms()]

    idx_nodes.sort()  # Sort by ind to ensure same order as rd_kit

    idx, nodes = zip(*idx_nodes)

    idx, nodes = list(zip(*idx_nodes))

    # Stack nodes into an array

    nodes = np.vstack(nodes)

    # second colum telling the size of each degree block

    # Input for tensorflow 

    deg_slice = np.array(zip(deg_start, deg_sizes))

    deg_slice = np.array(list(zip(deg_start, deg_sizes)))

    # Determines the membership (atom i belongs to membership[i] molecule)

    membership = [k