code: def multi_line(two_line_gdf):
      """Create a multi-line GeoDataFrame.
      This GDF has one multiline and one regular line."""
      # Create a single and multi line object
      multiline_feat = two_line_gdf.union_all()
      linec = LineString([(2, 1), (3, 1), (4, 1), (5, 2)])
      out_df = GeoDataFrame(
          geometry=GeoSeries([multiline_feat, linec]), crs="EPSG:3857"
      )
      out_df["attr"] = ["road", "stream"]
      return out_df
  
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 14 for calling a global function with example usage: multi_line(two_line_gdf) and returns: out_df