def METHOD_NAME(file_name):
  a = iotbx.xplor.map.reader(file_name=file_name)
  assert a.title_lines == [
    ' REMARKS FILENAME="cns.map"',
    ' REMARKS DATE:15-May-2004  02:15:56       created by user: rwgk',
    ' REMARKS VERSION:1.1']
  assert a.gridding.n == (24,24,40)
  assert a.gridding.first == (1,-4,-6)
  assert a.gridding.last == (10,0,-3)
  assert a.unit_cell.is_similar_to(
    uctbx.unit_cell((7.41407939496,7.41407939496,12.6039349714,90,90,120)))
  assert approx_equal(a.average, -0.5274E-10)
  assert approx_equal(a.standard_deviation, 0.1792E+00)
  assert a.data.origin() == (1,-4,-6)
  assert a.data.last(False) == (10,0,-3)
  assert a.data.focus() == (11,1,-2)
  assert approx_equal(a.data[:10],
    [-2.63210E-01, -4.36970E-01, -5.71930E-01, -6.09230E-01, -2.07220E-01,
     -4.15100E-01, -6.11970E-01, -7.13380E-01, -2.05500E-01, -3.60990E-01])
  assert approx_equal(a.data[40:50],
    [-4.08540E-01, -4.77320E-01, -5.16210E-01, -4.84100E-01, -2.93930E-01,
     -3.58500E-01, -4.40170E-01, -4.92110E-01, -2.19660E-01, -2.40570E-01])
  assert approx_equal(a.data[-10:],
    [-2.13550E-01, -4.87250E-01, -4.51260E-02, -2.13540E-01, -4.57070E-01,
     -6.38040E-01, -3.51570E-01, -5.98030E-01, -7.60270E-01, -7.62940E-01])
  stats = maptbx.statistics(a.data)
  assert approx_equal(stats.min(), -0.78098)
  assert approx_equal(stats.max(), 0.27233)
  assert approx_equal(stats.mean(), -0.363687)
  assert approx_equal(stats.sigma(), 0.20679)
  s = StringIO()
  a.show_summary(out=s, prefix="$")
  assert not show_diff(s.getvalue(), """\