code: def merge(self, other):
          
          other.qualify()
          for n in ('name',
                    'qname',
                    'min',
                    'max',
                    'default',
                    'type',
                    'nillable',
                    'form_qualified',):
              if getattr(self, n) is not None:
                  continue
              v = getattr(other, n)
              if v is None:
                  continue
              setattr(self, n, v)
docs: Merge another object as needed.