def CalculateAverageMolWeight(mol):
    """
    Calculation of average molecular weight. Note that not including H
        Parameters:
            mol: rdkit molecule
        Returns:
            AvgMolWeight: Average Molecular weight
    """
    MolWeight = 0
    for atom in mol.GetAtoms():
        MolWeight = MolWeight + atom.GetMass()
    return MolWeight / mol.GetNumAtoms()