code: def test_length_factors(
      self, xp, scp, len_h, len_x, up, down, expected
  ):
      # gh-9844: weird factors
      h = xp.zeros(len_h)
      h[0] = 1.0
      x = xp.ones(len_x)
      y = scp.signal.upfirdn(h, x, up, down)
      return y
  
file_path: cupy/tests/cupyx_tests/scipy_tests/signal_tests/test_upfirdn.py
imports: from itertools import product
  import pytest
  import numpy
  from cupy import testing
  from cupyx.scipy.signal._upfirdn import _output_len
label_desc: Use image node_id 3 for calling the TestUpfirdn obj's underlying member method code with example usage: obj.test_length_factors(xp, scp, len_h, len_x, up, down, expected) and returns: y