code: def test_stream_head():
      c1 = Counter().rename("c1")
  
      with NameSpace("world"):
          c2 = Counter().rename("c1")
  
      assert c1.name == "c1"
      assert c2.name == "world:/c1"
  
file_path: tensortrade/tests/tensortrade/unit/feed/core/test_base.py
imports: from tensortrade.feed.core import Stream, NameSpace
  from tensortrade.feed.core.base import Placeholder
label_desc: Use image node_id 2 for calling a global function with example usage: test_stream_head() without return types