code: def test_scalar(self):
      P = BarycentricInterpolator(self.xs, self.ys)
      assert_almost_equal(self.true_poly(7), P(7))
      assert_almost_equal(self.true_poly(np.array(7)), P(np.array(7)))
  
imports: import warnings
  import io
  import numpy
  from numpy.testing import assert_almost_equal, assert_array_equal, assert_array_almost_equal, assert_allclose, assert_equal, assert_
  from pytest import raises
  from scipy.interpolate import KroghInterpolator, krogh_interpolate, BarycentricInterpolator, barycentric_interpolate, approximate_taylor_polynomial, CubicHermiteSpline, pchip, PchipInterpolator, pchip_interpolate, Akima1DInterpolator, CubicSpline, make_interp_spline
label_desc: Use image node_id 3 for calling the TestBarycentric obj's underlying member method code with example usage: obj.test_scalar() without return types