code: def _check_primitive(null, null_ans):
      """Check that the primitive of the answer matches."""
      null = _to_DM(null, null_ans)
      cont, null_prim = null.primitive()
      assert null_prim == null_ans
  
file_path: sympy/sympy/polys/matrices/tests/test_nullspace.py
imports: from sympy import ZZ, Matrix
  from sympy.polys.matrices import DM, DomainMatrix
  from sympy.polys.matrices.ddm import DDM
  from sympy.polys.matrices.sdm import SDM
  import pytest
label_desc: Use image node_id 3 for calling a global function with example usage: _check_primitive(null, null_ans) without return types