def get_strict_smarts_for_atom(atom):
    """
    For an RDkit atom object, generate a simple SMARTS pattern.

    Parameters
    ----------
    atom: rdkit.Chem.Atom
        RDKit atom.

    Results
    -------
    symbol: str
        SMARTS symbol of the atom.
    """

    symbol = atom.GetSmarts()
    if "[" not in symbol:
        symbol = "[" + symbol + "]"

    return symbol