docstr: Test the correct warnings are raised if keep_geom_type is
  called on a mixed GDF
code: def test_warning_extra_geoms_mixed(self, mixed_gdf, mask):
      """Test the correct warnings are raised if keep_geom_type is
      called on a mixed GDF"""
      with pytest.warns(UserWarning):
          clip(mixed_gdf, mask, keep_geom_type=True)
  
imports: import numpy
  import shapely
  from shapely.geometry import Polygon, Point, LineString, LinearRing, GeometryCollection, MultiPoint, box
  import geopandas
  from geopandas import GeoDataFrame, GeoSeries, clip
  from geopandas.testing import assert_geodataframe_equal, assert_geoseries_equal
  import pytest
  from geopandas.tools.clip import _mask_is_list_like_rectangle
label_desc: Use image node_id 18 for calling the TestClipWithSingleRectangleGdf obj's underlying member method code with example usage: obj.test_warning_extra_geoms_mixed(mixed_gdf, mask) without return types