docs: def set_fields(self, fields=None, *fields_args, **fields_kwargs):
          """
          completely replaces the current .fields with fields and fields_kwargs combined
          """
          if fields_args:
              fields = [fields]
              fields.extend(fields_args)
              for field_name in fields:
                  self.set_field(field_name)
  
          elif fields_kwargs:
              fields = make_dict(fields, fields_kwargs)
              for field_name, field_val in fields.items():
                  self.set_field(field_name, field_val)
  
          else:
              if isinstance(fields, Mapping):
                  for field_name, field_val in fields.items():
                      self.set_field(field_name, field_val)
  
              else:
                  for field_name in fields:
                      self.set_field(field_name)
  
          return self