          # ListField.
          if isinstance(field, serializers.ListField):
              mapping = {
                  'type': 'array',
              }
              if not isinstance(field.child, _UnvalidatedField):
                  mapping['items'] = {
                      "type": self._map_field(field.child).get('type')
 
</s> remove             return {
 </s> add             mapping = { </s> remove from rest_framework.fields import empty
 </s> add from rest_framework.fields import _UnvalidatedField, empty
                'items': {},
          # ListField.
          if isinstance(field, serializers.ListField):
              mapping = {
                  'type': 'array',
                'items': {},
              }
              if not isinstance(field.child, _UnvalidatedField):
                  mapping['items'] = {
                      "type": self._map_field(field.child).get('type')
keep keep keep add keep keep keep keep
 Added mapping of ListField.child type for OpenAPI Schemas. 
rest_framework/schemas/openapi.py