code: def test_isinvertible(eg_cmaps):
      assert not eg_cmaps.a.inverse()
      assert eg_cmaps.b.inverse()
      assert not eg_cmaps.c.inverse()
      assert eg_cmaps.d.inverse()
      assert eg_cmaps.e.inverse()
      assert eg_cmaps.mapping.inverse()
      assert not eg_cmaps.singular.inverse()
  
imports: from copy import copy
  from types import SimpleNamespace
  import numpy
  from ..coordinate_map import AffineTransform, AxisError, CoordinateMap, CoordMapMaker, CoordMapMakerError, _as_coordinate_map, _fix0, append_io_dim, axmap, compose, drop_io_dim, equivalent, input_axis_index, io_axis_indices, orth_axes, product, shifted_domain_origin, shifted_range_origin
  from ..coordinate_system import CoordinateSystem, CoordinateSystemError, CoordSysMaker
  import pytest
  from numpy.testing import assert_almost_equal, assert_array_equal
label_desc: Use image node_id 9 for calling a global function with example usage: test_isinvertible(eg_cmaps) without return types