code: def test_push_duplicate(self):
      to_push = [2, 1, 0]
      h_sifted = [0, 2, 1]
      q = MappedQueue()
      for elt in to_push:
          inserted = q.push(elt)
          assert inserted
      assert q.heap == h_sifted
      self._check_map(q)
      inserted = q.push(1)
      assert not inserted
  
imports: import pytest
  from networkx.utils.mapped_queue import MappedQueue, _HeapElement
label_desc: Use image node_id 17 for calling the TestMappedQueue obj's underlying member method code with example usage: obj.test_push_duplicate() without return types