docs: def union_update(self, *others):
          r"""Update the multiset, adding elements from all others using the maximum multiplicity.
  
          >>> ms = Multiset('aab')
          >>> ms.union_update('bc')
          >>> sorted(ms)
          ['a', 'a', 'b', 'c']
  
          You can also use the ``|=`` operator for the same effect. However, the operator version
          will only accept a set as other operator, not any iterable, to avoid errors.
  
          >>> ms = Multiset('aab')
          >>> ms |= Multiset('bccd')
          >>> sorted(ms)
          ['a', 'a', 'b', 'c', 'c', 'd']
  
          For a variant of the operation which does not modify the multiset, but returns a new
          multiset instead see :meth:`union`.
  
          Args:
              others: The other sets to union this multiset with. Can also be any :class:`~typing.Iterable`\[~T]
                  or :class:`~typing.Mapping`\[~T, :class:`int`] which are then converted to :class:`Multiset`\[~T].
          """
          _elements = self._elements
          _total = self._total
          for other in map(self._as_mapping, others):
              for element, multiplicity in other.items():
                  old_multiplicity = _elements.get(element, 0)
                  if multiplicity > old_multiplicity:
                      _elements[element] = multiplicity
                      _total += multiplicity - old_multiplicity
          self._total = _total