def standardize_unit(u: str) -> str:
    """
    Helper method to convert typically seen unit representations into a
    standardized representation from QUDT
    (http://www.qudt.org/doc/DOC_VOCAB-UNITS.html). This is
    non-exhaustive, and may need to be updated as more types of units are
    encountered

    Args:
        u: The unit representation to convert

    Returns:
        The unit in a QUDT-standard representation (if known; otherwise just
        returns the unit representation as provided)
    """
    mapping = {
        # length
        'km': 'KiloM', 'cm': 'CentiM', 'm': 'M', 'mm': 'MilliM',
        'µm': 'MicroM', 'um': 'MicroM', 'nm': 'NanoM', 'pm': 'PicoM',
        'Å': 'ANGSTROM',
        # current
        'A': 'A', 'mA': 'MilliA', 'nA': 'NanoA', 'pA': 'PicoA',
        'µA': 'MicroA', 'uA': 'MicroA',
        # energy
        'eV': 'EV', 'GeV': 'GigaEV', 'keV': 'KiloEV', 'MeV': 'MegaEV',
        # mass
        'g': 'GM', 'kg': 'KiloGM',
        # potential
        'V': 'V', 'kV': 'KiloV', 'MV': 'MegaV', 'mV': 'MilliV',
        'uV': 'MicroV', 'µV': 'MicroV',
        # inverse lengths
        '1/nm': 'PER-NanoM', '1/mm': 'PER-MilliM', '1/m': 'PER-M',
        '1/cm': 'PER-CentiM', '1/um': 'PER-MicroM', '1/µm': 'PER-MicroM',
        '1/pm': 'PER-PicoM'
    }
    if u in mapping:
        return mapping[u]
    else:
        return u