code: def temporal_graph():
      nodes = [1, 2, 3, 4, 5, 6]
      edges = [(1, 2, 5), (2, 3, 2), (2, 4, 10), (4, 5, 3), (4, 6, 12)]
      edge_cols = ["source", "target", "weight"]
      return StellarGraph(
          nodes=pd.DataFrame(index=nodes),
          edges=pd.DataFrame(edges, columns=edge_cols),
      )
  
file_path: stellargraph/tests/data/test_temporal_random_walker.py
imports: import pandas
  import pytest
  import numpy
  import networkx
  from stellargraph.data.explorer import TemporalRandomWalk
  from stellargraph.core.graph import StellarGraph
label_desc: Use image node_id 1 for calling a global function with example usage: temporal_graph() and returns: StellarGraph