code: def test_iadding_list_ggplot():
      lst = [
          geom_point(),
          geom_point(aes("x+1", "y+1")),
          xlab("x-label"),
          coord_trans(),
      ]
      g = ggplot()
      id_before = id(g)
      g += lst
      id_after = id(g)
      assert id_before == id_after
      assert len(g.layers) == 2
      assert g.labels.x == "x-label"
      assert isinstance(g.coordinates, coord_trans)
  
imports: from copy import deepcopy
  import numpy
  import pandas
  import pytest
  from plotnine import aes, after_scale, after_stat, annotate, coord_trans, facet_null, geom_bar, geom_histogram, geom_line, geom_point, ggplot, ggtitle, guides, labs, lims, scale_x_continuous, stage, stat_identity, theme, theme_gray, xlab, xlim, ylab
  from plotnine.exceptions import PlotnineError, PlotnineWarning
  from plotnine.mapping.aes import is_valid_aesthetic
label_desc: Use image node_id 18 for calling a global function with example usage: test_iadding_list_ggplot() without return types