  
      return fields
  
  
  def _get_forward_relationships(opts):
      """
      Returns an `OrderedDict` of field names to `RelationInfo`.
      """
      forward_relations = OrderedDict()
      for field in [field for field in opts.fields if field.serialize and field.rel]:
 
</s> remove     model_field, related_model, to_many, has_through_model = relation_info
 </s> add     model_field, related_model, to_many, to_field, has_through_model = relation_info
def _get_to_field(field):
    return field.to_fields[0] if field.to_fields else None


  
      return fields
  
  
def _get_to_field(field):
    return field.to_fields[0] if field.to_fields else None


  def _get_forward_relationships(opts):
      """
      Returns an `OrderedDict` of field names to `RelationInfo`.
      """
      forward_relations = OrderedDict()
      for field in [field for field in opts.fields if field.serialize and field.rel]:
keep keep keep add keep keep keep keep keep keep
 Added support for the to_field on ForeignKey fields 
rest_framework/utils/model_meta.py