code: def test_mul():
      expected = [2, 4, 6, 8, 10, 12]
  
      # (left, right) : (Stream, Stream)
      s1 = Stream.source([1, 2, 3, 4, 5, 6], dtype="float")
      s2 = Stream.source([2, 2, 2, 2, 2, 2], dtype="float")
  
      w1 = s1.mul(s2).rename("w1")
      w2 = (s1 * s2).rename("w2")
  
      assert_op([w1, w2], expected)
  
      # (left, right) : (Stream, float)
      w1 = s1.mul(2).rename("w1")
      w2 = (s1 * 2).rename("w2")
  
      assert_op([w1, w2], expected)
  
file_path: tensortrade/tests/tensortrade/unit/feed/api/float/test_operations.py
imports: import pandas
  from tensortrade.feed import Stream
  from tests.utils.ops import assert_op
label_desc: Use image node_id 5 for calling a global function with example usage: test_mul() without return types