code: def test_fmtloc(self):
      class DummyAxis:
          def __init__(self):
              self.fields = {}
  
          def set(self, **kwargs):
              self.fields.update(**kwargs)
  
          def set_major_formatter(self, f):
              self.fields["major_formatter"] = f
  
      ax0 = DummyAxis()
      s0 = AsinhScale(axis=ax0, base=0)
      s0.set_default_locators_and_formatters(ax0)
      assert isinstance(ax0.fields["major_locator"], AsinhLocator)
      assert isinstance(ax0.fields["major_formatter"], str)
  
      ax5 = DummyAxis()
      s7 = AsinhScale(axis=ax5, base=5)
      s7.set_default_locators_and_formatters(ax5)
      assert isinstance(ax5.fields["major_locator"], AsinhLocator)
      assert isinstance(
          ax5.fields["major_formatter"], LogFormatterSciNotation
      )
  
imports: import copy
  import matplotlib.pyplot
  from matplotlib.scale import AsinhScale, AsinhTransform, LogTransform, InvertedLogTransform, SymmetricalLogTransform
  import matplotlib.scale
  from matplotlib.ticker import AsinhLocator, LogFormatterSciNotation
  from matplotlib.testing.decorators import check_figures_equal, image_comparison
  import numpy
  from numpy.testing import assert_allclose
  import io
  import pytest
label_desc: Use image node_id 4 for calling the TestAsinhScale obj's underlying member method code with example usage: obj.test_fmtloc() without return types