code: def _vertex_list_to_dataframe(ls, id_column_name):
      """
      Convert a list of vertices into dataframe.
      """
      assert (
          HAS_PANDAS
      ), "Cannot use dataframe because Pandas is not available or version is too low."
      cols = reduce(set.union, (set(v.attr.keys()) for v in ls))
      df = pd.DataFrame({id_column_name: [v.vid for v in ls]})
      for c in cols:
          df[c] = [v.attr.get(c) for v in ls]
      return df
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  from .._connect import main
  from .sframe import SFrame
  from .sarray import SArray
  from .gframe import GFrame, VERTEX_GFRAME, EDGE_GFRAME
  from .._cython.cy_graph import UnityGraphProxy
  from .._cython.context import debug_trace
  from ..util import _is_non_string_iterable, _make_internal_url
  from .._deps import pandas
  from .._deps import HAS_PANDAS
  import inspect
  import copy
  import sys
label_desc: Use image node_id 2 for calling a global function with example usage: _vertex_list_to_dataframe(ls, id_column_name) and returns: df