code: def test_recoder_1():
      # simplest case, no aliases
      codes = ((1,), (2,))
      rc = Recoder(codes)
      assert rc.code[1] == 1
      assert rc.code[2] == 2
      with pytest.raises(KeyError):
          rc.code[3]
  
file_path: nibabel/nibabel/tests/test_recoder.py
imports: import numpy
  import pytest
  from ..volumeutils import DtypeMapper, Recoder, native_code, swapped_code
label_desc: Use image node_id 1 for calling a global function with example usage: test_recoder_1() without return types