def METHOD_NAME(element: "pt.Element") -> "pt.Isotope":
    """Given a `periodictable` element, return the most abundant
    isotope.
    """
    most_abundant_isotope = element.isotopes[0]
    abundance = 0
    for iso in element:
        if iso.abundance > abundance:
            most_abundant_isotope = iso
            abundance = iso.abundance
    return most_abundant_isotope