code: def test_coefficient_properties(solver):
      assert_allclose(np.sum(solver.B), 1, rtol=1e-15)
      assert_allclose(np.sum(solver.A, axis=1), solver.C, rtol=1e-14)
  
file_path: catboost/contrib/python/scipy/py3/scipy/integrate/_ivp/tests/test_rk.py
imports: import pytest
  from numpy.testing import assert_allclose, assert_
  import numpy
  from scipy.integrate import RK23, RK45, DOP853
  from scipy.integrate._ivp import dop853_coefficients
label_desc: Use image node_id 1 for calling a global function with example usage: test_coefficient_properties(solver) without return types