code: def test_gridliner_default_fmtloc(
      proj, gcrs, xloc, xfmt, xloc_expected, xfmt_expected
  ):
      fig = plt.figure()
      ax = fig.add_subplot(1, 1, 1, projection=proj)
      gl = ax.gridlines(
          crs=gcrs, draw_labels=False, xlocs=xloc, xformatter=xfmt
      )
      assert isinstance(gl.xlocator, xloc_expected)
      assert isinstance(gl.xformatter, xfmt_expected)
  
imports: import io
  from unittest import mock
  from matplotlib.collections import PolyCollection
  import matplotlib.pyplot
  import matplotlib.ticker
  import numpy
  import pytest
  from shapely.geos import geos_version
  import cartopy.crs
  from cartopy.mpl import _MPL_36
  from cartopy.mpl.geoaxes import GeoAxes
  from cartopy.mpl.gridliner import LATITUDE_FORMATTER, LONGITUDE_FORMATTER, Gridliner, classic_formatter, classic_locator
  from cartopy.mpl.ticker import LongitudeFormatter, LongitudeLocator
label_desc: Use image node_id 9 for calling a global function with example usage: test_gridliner_default_fmtloc(proj, gcrs, xloc, xfmt, xloc_expected, xfmt_expected) without return types