docstr: Test if wlen actually shrinks the evaluation range correctly.
code: def test_wlen(self):
      """
      Test if wlen actually shrinks the evaluation range correctly.
      """
      x = [0, 1, 2, 3, 1, 0, -1]
      peak = [3]
      # Test rounding behavior of wlen
      assert_equal(peak_prominences(x, peak), [3.0, 0, 6])
      for wlen, i in [
          (8, 0),
          (7, 0),
          (6, 0),
          (5, 1),
          (3.2, 1),
          (3, 2),
          (1.1, 2),
      ]:
          assert_equal(
              peak_prominences(x, peak, wlen), [3.0 - i, 0 + i, 6 - i]
          )
  
imports: import copy
  import numpy
  from numpy.testing import assert_, assert_equal, assert_allclose, assert_array_equal
  import pytest
  from pytest import raises, warns
  from scipy.signal._peak_finding import argrelmax, argrelmin, peak_prominences, peak_widths, _unpack_condition_args, find_peaks, find_peaks_cwt, _identify_ridge_lines
  from scipy.signal._peak_finding_utils import _local_maxima_1d, PeakPropertyWarning
label_desc: Use image node_id 5 for calling the TestPeakProminences obj's underlying member method code with example usage: obj.test_wlen() without return types