code: def check_lstsq_solution(
      self, a_shape, b_shape, seed, rcond, xp, dtype, singular=False
  ):
      if singular:
          m, n = a_shape
          rank = min(m, n) - 1
          a = xp.matmul(
              testing.shaped_random(
                  (m, rank), xp, dtype=dtype, scale=3, seed=seed
              ),
              testing.shaped_random(
                  (rank, n), xp, dtype=dtype, scale=3, seed=seed + 42
              ),
          )
      else:
          a = testing.shaped_random(a_shape, xp, dtype=dtype, seed=seed)
      b = testing.shaped_random(
          b_shape, xp, dtype=dtype, seed=seed + 37
      )
      a_copy = a.copy()
      b_copy = b.copy()
      results = xp.linalg.lstsq(a, b, rcond)
      if xp is cupy:
          testing.assert_array_equal(a_copy, a)
          testing.assert_array_equal(b_copy, b)
      return results
  
imports: import unittest
  import numpy
  import pytest
  import cupy
  from cupy import testing
  from cupy.testing import _condition
  import cupyx
  from cupy.cublas import get_batched_gesv_limit, set_batched_gesv_limit
label_desc: Use image node_id 1 for calling the TestLstsq obj's underlying member method code with example usage: obj.check_lstsq_solution(a_shape, b_shape, seed, rcond, xp, dtype, singular) and returns: results