code: def test_reduce():
      point = Tensor(randn(3))
      d = Delta("foo", point)
      assert d.reduce(ops.logaddexp, frozenset(["foo"])) is Number(0)
  
file_path: funsor/test/test_delta.py
imports: import pytest
  import funsor.ops
  from funsor.delta import Delta
  from funsor.domains import Real, Reals
  from funsor.tensor import Tensor, numeric_array
  from funsor.terms import Number, Variable
  from funsor.testing import assert_close, check_funsor, randn
label_desc: Use image node_id 4 for calling a global function with example usage: test_reduce() without return types