code: def testToDirectedAcyclic(self):
      graph = Graph(
          [(0, 1), (2, 0), (3, 0), (3, 0), (4, 2)], directed=False
      )
      graph.to_directed("acyclic")
      self.assertTrue(graph.is_directed())
      self.assertTrue(graph.vcount() == 5)
      self.assertTrue(
          sorted(graph.get_edgelist())
          == [(0, 1), (0, 2), (0, 3), (0, 3), (2, 4)]
      )
  
file_path: python-igraph/tests/test_conversion.py
imports: import random
  import unittest
  from igraph import Graph, Matrix
label_desc: Use image node_id 4 for calling the DirectedUndirectedTests obj's underlying member method code with example usage: obj.testToDirectedAcyclic() without return types