code: def argmin(x, axis):
      """
      Args:
          x (numpy.ndarray): Input array.
          axis (:obj:`tuple` of :obj:`int`): Argmin along these axes.
      """
      return preprocess_arg_reduction(x, axis).argmin(-1)
  
file_path: nnabla/python/test/function/test_reduction.py
imports: import pytest
  import numpy
  import nnabla
  import nnabla.functions
  from nnabla.testing import assert_allclose
  from nbla_test_utils import function_tester, list_context, list_ctx_and_func_name
label_desc: Use image node_id 6 for calling a global function with example usage: argmin(x, axis) and returns: preprocess_arg_reduction