code: def test_metrics():
      check_metric("acc", axis=0)
      check_metric("f1")
      check_metric("mcc")
      check_metric("perplexity", axis=-1)
      check_metric("pearsonr")
      check_metric("pcc")
      check_metric("ce")
      check_metric("loss")
      composite = mx.gluon.metric.create(["acc", "f1"])
      check_metric(composite)
  
imports: import mxnet
  from mxnet.test_utils import use_np
  import numpy
  import scipy
  from scipy.stats import pearsonr
  import json
  import math
  from common import xfail_when_nonstandard_decimal_separator
  from copy import deepcopy
label_desc: Use image node_id 2 for calling a global function with example usage: test_metrics() without return types