Update this dictionary with the items from <mapping>, replacing
        existing key:value items with shared keys before adding new key:value
        items.

        Example:
          omd = omdict([(1,1), (2,2)])
          omd.updateall([(2,'two'), (1,'one'), (2,222), (1,111)])
          omd.allitems() == [(1, 'one'), (2, 'two'), (2, 222), (1, 111)]

        Returns: <self>.

def updateall(self, *args, **kwargs):
        """
        Update this dictionary with the items from <mapping>, replacing
        existing key:value items with shared keys before adding new key:value
        items.

        Example:
          omd = omdict([(1,1), (2,2)])
          omd.updateall([(2,'two'), (1,'one'), (2,222), (1,111)])
          omd.allitems() == [(1, 'one'), (2, 'two'), (2, 222), (1, 111)]

        Returns: <self>.
        """
        self._update_updateall(False, *args, **kwargs)
        return self